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-rw-r--r--drivers/i2c/Kconfig13
-rw-r--r--drivers/i2c/Makefile3
-rw-r--r--drivers/i2c/busses/Kconfig24
-rw-r--r--drivers/i2c/busses/Makefile1
-rw-r--r--drivers/i2c/busses/i2c-cpm.c14
-rw-r--r--drivers/i2c/busses/i2c-davinci.c314
-rw-r--r--drivers/i2c/busses/i2c-ibm_iic.c10
-rw-r--r--drivers/i2c/busses/i2c-mpc.c75
-rw-r--r--drivers/i2c/busses/i2c-nuc900.c709
-rw-r--r--drivers/i2c/busses/i2c-pxa.c2
-rw-r--r--drivers/i2c/busses/i2c-sh_mobile.c121
-rw-r--r--drivers/i2c/i2c-core.c167
-rw-r--r--drivers/i2c/i2c-dev.c66
-rw-r--r--drivers/i2c/i2c-mux.c165
-rw-r--r--drivers/i2c/muxes/Kconfig18
-rw-r--r--drivers/i2c/muxes/Makefile8
-rw-r--r--drivers/i2c/muxes/pca954x.c301
17 files changed, 1804 insertions, 207 deletions
diff --git a/drivers/i2c/Kconfig b/drivers/i2c/Kconfig
index d06083f..30f06e9 100644
--- a/drivers/i2c/Kconfig
+++ b/drivers/i2c/Kconfig
@@ -47,6 +47,19 @@ config I2C_CHARDEV
This support is also available as a module. If so, the module
will be called i2c-dev.
+config I2C_MUX
+ tristate "I2C bus multiplexing support"
+ depends on EXPERIMENTAL
+ help
+ Say Y here if you want the I2C core to support the ability to
+ handle multiplexed I2C bus topologies, by presenting each
+ multiplexed segment as a I2C adapter.
+
+ This support is also available as a module. If so, the module
+ will be called i2c-mux.
+
+source drivers/i2c/muxes/Kconfig
+
config I2C_HELPER_AUTO
bool "Autoselect pertinent helper modules"
default y
diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile
index a7d9b4be9..c00fd66 100644
--- a/drivers/i2c/Makefile
+++ b/drivers/i2c/Makefile
@@ -6,7 +6,8 @@ obj-$(CONFIG_I2C_BOARDINFO) += i2c-boardinfo.o
obj-$(CONFIG_I2C) += i2c-core.o
obj-$(CONFIG_I2C_SMBUS) += i2c-smbus.o
obj-$(CONFIG_I2C_CHARDEV) += i2c-dev.o
-obj-y += algos/ busses/
+obj-$(CONFIG_I2C_MUX) += i2c-mux.o
+obj-y += algos/ busses/ muxes/
ifeq ($(CONFIG_I2C_DEBUG_CORE),y)
EXTRA_CFLAGS += -DDEBUG
diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index bceafbf..6539ac2 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -448,6 +448,13 @@ config I2C_NOMADIK
If you say yes to this option, support will be included for the
I2C interface from ST-Ericsson's Nomadik and Ux500 architectures.
+config I2C_NUC900
+ tristate "NUC900 I2C Driver"
+ depends on ARCH_W90X900
+ help
+ Say Y here to include support for I2C controller in the
+ Winbond/Nuvoton NUC900 based System-on-Chip devices.
+
config I2C_OCORES
tristate "OpenCores I2C Controller"
depends on EXPERIMENTAL
@@ -496,8 +503,8 @@ config I2C_PMCMSP
will be called i2c-pmcmsp.
config I2C_PNX
- tristate "I2C bus support for Philips PNX targets"
- depends on ARCH_PNX4008
+ tristate "I2C bus support for Philips PNX and NXP LPC targets"
+ depends on ARCH_PNX4008 || ARCH_LPC32XX
help
This driver supports the Philips IP3204 I2C IP block master and/or
slave controller
@@ -521,12 +528,19 @@ config I2C_PXA_SLAVE
is necessary for systems where the PXA may be a target on the
I2C bus.
+config HAVE_S3C2410_I2C
+ bool
+ help
+ This will include I2C support for Samsung SoCs. If you want to
+ include I2C support for any machine, kindly select this in the
+ respective Kconfig file.
+
config I2C_S3C2410
tristate "S3C2410 I2C Driver"
- depends on ARCH_S3C2410 || ARCH_S3C64XX
+ depends on HAVE_S3C2410_I2C
help
Say Y here to include support for I2C controller in the
- Samsung S3C2410 based System-on-Chip devices.
+ Samsung SoCs.
config I2C_S6000
tristate "S6000 I2C support"
@@ -549,7 +563,7 @@ config I2C_SH7760
config I2C_SH_MOBILE
tristate "SuperH Mobile I2C Controller"
- depends on SUPERH
+ depends on SUPERH || ARCH_SHMOBILE
help
If you say yes to this option, support will be included for the
built-in I2C interface on the Renesas SH-Mobile processor.
diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
index 936880b..c3ef492 100644
--- a/drivers/i2c/busses/Makefile
+++ b/drivers/i2c/busses/Makefile
@@ -43,6 +43,7 @@ obj-$(CONFIG_I2C_IXP2000) += i2c-ixp2000.o
obj-$(CONFIG_I2C_MPC) += i2c-mpc.o
obj-$(CONFIG_I2C_MV64XXX) += i2c-mv64xxx.o
obj-$(CONFIG_I2C_NOMADIK) += i2c-nomadik.o
+obj-$(CONFIG_I2C_NUC900) += i2c-nuc900.o
obj-$(CONFIG_I2C_OCORES) += i2c-ocores.o
obj-$(CONFIG_I2C_OMAP) += i2c-omap.o
obj-$(CONFIG_I2C_PASEMI) += i2c-pasemi.o
diff --git a/drivers/i2c/busses/i2c-cpm.c b/drivers/i2c/busses/i2c-cpm.c
index b02b453..f7bd261 100644
--- a/drivers/i2c/busses/i2c-cpm.c
+++ b/drivers/i2c/busses/i2c-cpm.c
@@ -105,7 +105,7 @@ struct i2c_reg {
struct cpm_i2c {
char *base;
- struct of_device *ofdev;
+ struct platform_device *ofdev;
struct i2c_adapter adap;
uint dp_addr;
int version; /* CPM1=1, CPM2=2 */
@@ -428,7 +428,7 @@ static const struct i2c_adapter cpm_ops = {
static int __devinit cpm_i2c_setup(struct cpm_i2c *cpm)
{
- struct of_device *ofdev = cpm->ofdev;
+ struct platform_device *ofdev = cpm->ofdev;
const u32 *data;
int len, ret, i;
void __iomem *i2c_base;
@@ -634,7 +634,7 @@ static void cpm_i2c_shutdown(struct cpm_i2c *cpm)
cpm_muram_free(cpm->i2c_addr);
}
-static int __devinit cpm_i2c_probe(struct of_device *ofdev,
+static int __devinit cpm_i2c_probe(struct platform_device *ofdev,
const struct of_device_id *match)
{
int result, len;
@@ -652,6 +652,7 @@ static int __devinit cpm_i2c_probe(struct of_device *ofdev,
cpm->adap = cpm_ops;
i2c_set_adapdata(&cpm->adap, cpm);
cpm->adap.dev.parent = &ofdev->dev;
+ cpm->adap.dev.of_node = of_node_get(ofdev->dev.of_node);
result = cpm_i2c_setup(cpm);
if (result) {
@@ -676,11 +677,6 @@ static int __devinit cpm_i2c_probe(struct of_device *ofdev,
dev_dbg(&ofdev->dev, "hw routines for %s registered.\n",
cpm->adap.name);
- /*
- * register OF I2C devices
- */
- of_register_i2c_devices(&cpm->adap, ofdev->dev.of_node);
-
return 0;
out_shut:
cpm_i2c_shutdown(cpm);
@@ -691,7 +687,7 @@ out_free:
return result;
}
-static int __devexit cpm_i2c_remove(struct of_device *ofdev)
+static int __devexit cpm_i2c_remove(struct platform_device *ofdev)
{
struct cpm_i2c *cpm = dev_get_drvdata(&ofdev->dev);
diff --git a/drivers/i2c/busses/i2c-davinci.c b/drivers/i2c/busses/i2c-davinci.c
index 4523364..2222c87 100644
--- a/drivers/i2c/busses/i2c-davinci.c
+++ b/drivers/i2c/busses/i2c-davinci.c
@@ -36,14 +36,16 @@
#include <linux/platform_device.h>
#include <linux/io.h>
#include <linux/slab.h>
+#include <linux/cpufreq.h>
+#include <linux/gpio.h>
#include <mach/hardware.h>
-
#include <mach/i2c.h>
/* ----- global defines ----------------------------------------------- */
#define DAVINCI_I2C_TIMEOUT (1*HZ)
+#define DAVINCI_I2C_MAX_TRIES 2
#define I2C_DAVINCI_INTR_ALL (DAVINCI_I2C_IMR_AAS | \
DAVINCI_I2C_IMR_SCD | \
DAVINCI_I2C_IMR_ARDY | \
@@ -72,37 +74,29 @@
#define DAVINCI_I2C_IVR_NACK 0x02
#define DAVINCI_I2C_IVR_AL 0x01
-#define DAVINCI_I2C_STR_BB (1 << 12)
-#define DAVINCI_I2C_STR_RSFULL (1 << 11)
-#define DAVINCI_I2C_STR_SCD (1 << 5)
-#define DAVINCI_I2C_STR_ARDY (1 << 2)
-#define DAVINCI_I2C_STR_NACK (1 << 1)
-#define DAVINCI_I2C_STR_AL (1 << 0)
-
-#define DAVINCI_I2C_MDR_NACK (1 << 15)
-#define DAVINCI_I2C_MDR_STT (1 << 13)
-#define DAVINCI_I2C_MDR_STP (1 << 11)
-#define DAVINCI_I2C_MDR_MST (1 << 10)
-#define DAVINCI_I2C_MDR_TRX (1 << 9)
-#define DAVINCI_I2C_MDR_XA (1 << 8)
-#define DAVINCI_I2C_MDR_RM (1 << 7)
-#define DAVINCI_I2C_MDR_IRS (1 << 5)
-
-#define DAVINCI_I2C_IMR_AAS (1 << 6)
-#define DAVINCI_I2C_IMR_SCD (1 << 5)
-#define DAVINCI_I2C_IMR_XRDY (1 << 4)
-#define DAVINCI_I2C_IMR_RRDY (1 << 3)
-#define DAVINCI_I2C_IMR_ARDY (1 << 2)
-#define DAVINCI_I2C_IMR_NACK (1 << 1)
-#define DAVINCI_I2C_IMR_AL (1 << 0)
-
-#define MOD_REG_BIT(val, mask, set) do { \
- if (set) { \
- val |= mask; \
- } else { \
- val &= ~mask; \
- } \
-} while (0)
+#define DAVINCI_I2C_STR_BB BIT(12)
+#define DAVINCI_I2C_STR_RSFULL BIT(11)
+#define DAVINCI_I2C_STR_SCD BIT(5)
+#define DAVINCI_I2C_STR_ARDY BIT(2)
+#define DAVINCI_I2C_STR_NACK BIT(1)
+#define DAVINCI_I2C_STR_AL BIT(0)
+
+#define DAVINCI_I2C_MDR_NACK BIT(15)
+#define DAVINCI_I2C_MDR_STT BIT(13)
+#define DAVINCI_I2C_MDR_STP BIT(11)
+#define DAVINCI_I2C_MDR_MST BIT(10)
+#define DAVINCI_I2C_MDR_TRX BIT(9)
+#define DAVINCI_I2C_MDR_XA BIT(8)
+#define DAVINCI_I2C_MDR_RM BIT(7)
+#define DAVINCI_I2C_MDR_IRS BIT(5)
+
+#define DAVINCI_I2C_IMR_AAS BIT(6)
+#define DAVINCI_I2C_IMR_SCD BIT(5)
+#define DAVINCI_I2C_IMR_XRDY BIT(4)
+#define DAVINCI_I2C_IMR_RRDY BIT(3)
+#define DAVINCI_I2C_IMR_ARDY BIT(2)
+#define DAVINCI_I2C_IMR_NACK BIT(1)
+#define DAVINCI_I2C_IMR_AL BIT(0)
struct davinci_i2c_dev {
struct device *dev;
@@ -113,8 +107,13 @@ struct davinci_i2c_dev {
u8 *buf;
size_t buf_len;
int irq;
+ int stop;
u8 terminate;
struct i2c_adapter adapter;
+#ifdef CONFIG_CPU_FREQ
+ struct completion xfr_complete;
+ struct notifier_block freq_transition;
+#endif
};
/* default platform data to use if not supplied in the platform_device */
@@ -134,12 +133,59 @@ static inline u16 davinci_i2c_read_reg(struct davinci_i2c_dev *i2c_dev, int reg)
return __raw_readw(i2c_dev->base + reg);
}
-/*
- * This functions configures I2C and brings I2C out of reset.
- * This function is called during I2C init function. This function
- * also gets called if I2C encounters any errors.
+/* Generate a pulse on the i2c clock pin. */
+static void generic_i2c_clock_pulse(unsigned int scl_pin)
+{
+ u16 i;
+
+ if (scl_pin) {
+ /* Send high and low on the SCL line */
+ for (i = 0; i < 9; i++) {
+ gpio_set_value(scl_pin, 0);
+ udelay(20);
+ gpio_set_value(scl_pin, 1);
+ udelay(20);
+ }
+ }
+}
+
+/* This routine does i2c bus recovery as specified in the
+ * i2c protocol Rev. 03 section 3.16 titled "Bus clear"
*/
-static int i2c_davinci_init(struct davinci_i2c_dev *dev)
+static void i2c_recover_bus(struct davinci_i2c_dev *dev)
+{
+ u32 flag = 0;
+ struct davinci_i2c_platform_data *pdata = dev->dev->platform_data;
+
+ dev_err(dev->dev, "initiating i2c bus recovery\n");
+ /* Send NACK to the slave */
+ flag = davinci_i2c_read_reg(dev, DAVINCI_I2C_MDR_REG);
+ flag |= DAVINCI_I2C_MDR_NACK;
+ /* write the data into mode register */
+ davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, flag);
+ if (pdata)
+ generic_i2c_clock_pulse(pdata->scl_pin);
+ /* Send STOP */
+ flag = davinci_i2c_read_reg(dev, DAVINCI_I2C_MDR_REG);
+ flag |= DAVINCI_I2C_MDR_STP;
+ davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, flag);
+}
+
+static inline void davinci_i2c_reset_ctrl(struct davinci_i2c_dev *i2c_dev,
+ int val)
+{
+ u16 w;
+
+ w = davinci_i2c_read_reg(i2c_dev, DAVINCI_I2C_MDR_REG);
+ if (!val) /* put I2C into reset */
+ w &= ~DAVINCI_I2C_MDR_IRS;
+ else /* take I2C out of reset */
+ w |= DAVINCI_I2C_MDR_IRS;
+
+ davinci_i2c_write_reg(i2c_dev, DAVINCI_I2C_MDR_REG, w);
+}
+
+static void i2c_davinci_calc_clk_dividers(struct davinci_i2c_dev *dev)
{
struct davinci_i2c_platform_data *pdata = dev->dev->platform_data;
u16 psc;
@@ -148,15 +194,6 @@ static int i2c_davinci_init(struct davinci_i2c_dev *dev)
u32 clkh;
u32 clkl;
u32 input_clock = clk_get_rate(dev->clk);
- u16 w;
-
- if (!pdata)
- pdata = &davinci_i2c_platform_data_default;
-
- /* put I2C into reset */
- w = davinci_i2c_read_reg(dev, DAVINCI_I2C_MDR_REG);
- MOD_REG_BIT(w, DAVINCI_I2C_MDR_IRS, 0);
- davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, w);
/* NOTE: I2C Clock divider programming info
* As per I2C specs the following formulas provide prescaler
@@ -188,12 +225,32 @@ static int i2c_davinci_init(struct davinci_i2c_dev *dev)
davinci_i2c_write_reg(dev, DAVINCI_I2C_CLKH_REG, clkh);
davinci_i2c_write_reg(dev, DAVINCI_I2C_CLKL_REG, clkl);
+ dev_dbg(dev->dev, "input_clock = %d, CLK = %d\n", input_clock, clk);
+}
+
+/*
+ * This function configures I2C and brings I2C out of reset.
+ * This function is called during I2C init function. This function
+ * also gets called if I2C encounters any errors.
+ */
+static int i2c_davinci_init(struct davinci_i2c_dev *dev)
+{
+ struct davinci_i2c_platform_data *pdata = dev->dev->platform_data;
+
+ if (!pdata)
+ pdata = &davinci_i2c_platform_data_default;
+
+ /* put I2C into reset */
+ davinci_i2c_reset_ctrl(dev, 0);
+
+ /* compute clock dividers */
+ i2c_davinci_calc_clk_dividers(dev);
+
/* Respond at reserved "SMBus Host" slave address" (and zero);
* we seem to have no option to not respond...
*/
davinci_i2c_write_reg(dev, DAVINCI_I2C_OAR_REG, 0x08);
- dev_dbg(dev->dev, "input_clock = %d, CLK = %d\n", input_clock, clk);
dev_dbg(dev->dev, "PSC = %d\n",
davinci_i2c_read_reg(dev, DAVINCI_I2C_PSC_REG));
dev_dbg(dev->dev, "CLKL = %d\n",
@@ -204,9 +261,7 @@ static int i2c_davinci_init(struct davinci_i2c_dev *dev)
pdata->bus_freq, pdata->bus_delay);
/* Take the I2C module out of reset: */
- w = davinci_i2c_read_reg(dev, DAVINCI_I2C_MDR_REG);
- MOD_REG_BIT(w, DAVINCI_I2C_MDR_IRS, 1);
- davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, w);
+ davinci_i2c_reset_ctrl(dev, 1);
/* Enable interrupts */
davinci_i2c_write_reg(dev, DAVINCI_I2C_IMR_REG, I2C_DAVINCI_INTR_ALL);
@@ -221,14 +276,22 @@ static int i2c_davinci_wait_bus_not_busy(struct davinci_i2c_dev *dev,
char allow_sleep)
{
unsigned long timeout;
+ static u16 to_cnt;
timeout = jiffies + dev->adapter.timeout;
while (davinci_i2c_read_reg(dev, DAVINCI_I2C_STR_REG)
& DAVINCI_I2C_STR_BB) {
- if (time_after(jiffies, timeout)) {
- dev_warn(dev->dev,
- "timeout waiting for bus ready\n");
- return -ETIMEDOUT;
+ if (to_cnt <= DAVINCI_I2C_MAX_TRIES) {
+ if (time_after(jiffies, timeout)) {
+ dev_warn(dev->dev,
+ "timeout waiting for bus ready\n");
+ to_cnt++;
+ return -ETIMEDOUT;
+ } else {
+ to_cnt = 0;
+ i2c_recover_bus(dev);
+ i2c_davinci_init(dev);
+ }
}
if (allow_sleep)
schedule_timeout(1);
@@ -250,9 +313,6 @@ i2c_davinci_xfer_msg(struct i2c_adapter *adap, struct i2c_msg *msg, int stop)
u16 w;
int r;
- if (msg->len == 0)
- return -EINVAL;
-
if (!pdata)
pdata = &davinci_i2c_platform_data_default;
/* Introduce a delay, required for some boards (e.g Davinci EVM) */
@@ -264,6 +324,7 @@ i2c_davinci_xfer_msg(struct i2c_adapter *adap, struct i2c_msg *msg, int stop)
dev->buf = msg->buf;
dev->buf_len = msg->len;
+ dev->stop = stop;
davinci_i2c_write_reg(dev, DAVINCI_I2C_CNT_REG, dev->buf_len);
@@ -281,23 +342,40 @@ i2c_davinci_xfer_msg(struct i2c_adapter *adap, struct i2c_msg *msg, int stop)
flag |= DAVINCI_I2C_MDR_TRX;
if (stop)
flag |= DAVINCI_I2C_MDR_STP;
+ if (msg->len == 0) {
+ flag |= DAVINCI_I2C_MDR_RM;
+ flag &= ~DAVINCI_I2C_MDR_STP;
+ }
/* Enable receive or transmit interrupts */
w = davinci_i2c_read_reg(dev, DAVINCI_I2C_IMR_REG);
if (msg->flags & I2C_M_RD)
- MOD_REG_BIT(w, DAVINCI_I2C_IMR_RRDY, 1);
+ w |= DAVINCI_I2C_IMR_RRDY;
else
- MOD_REG_BIT(w, DAVINCI_I2C_IMR_XRDY, 1);
+ w |= DAVINCI_I2C_IMR_XRDY;
davinci_i2c_write_reg(dev, DAVINCI_I2C_IMR_REG, w);
dev->terminate = 0;
+
/* write the data into mode register */
davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, flag);
+ /*
+ * First byte should be set here, not after interrupt,
+ * because transmit-data-ready interrupt can come before
+ * NACK-interrupt during sending of previous message and
+ * ICDXR may have wrong data
+ */
+ if ((!(msg->flags & I2C_M_RD)) && dev->buf_len) {
+ davinci_i2c_write_reg(dev, DAVINCI_I2C_DXR_REG, *dev->buf++);
+ dev->buf_len--;
+ }
+
r = wait_for_completion_interruptible_timeout(&dev->cmd_complete,
dev->adapter.timeout);
if (r == 0) {
dev_err(dev->dev, "controller timed out\n");
+ i2c_recover_bus(dev);
i2c_davinci_init(dev);
dev->buf_len = 0;
return -ETIMEDOUT;
@@ -334,7 +412,7 @@ i2c_davinci_xfer_msg(struct i2c_adapter *adap, struct i2c_msg *msg, int stop)
return msg->len;
if (stop) {
w = davinci_i2c_read_reg(dev, DAVINCI_I2C_MDR_REG);
- MOD_REG_BIT(w, DAVINCI_I2C_MDR_STP, 1);
+ w |= DAVINCI_I2C_MDR_STP;
davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, w);
}
return -EREMOTEIO;
@@ -367,12 +445,17 @@ i2c_davinci_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
if (ret < 0)
return ret;
}
+
+#ifdef CONFIG_CPU_FREQ
+ complete(&dev->xfr_complete);
+#endif
+
return num;
}
static u32 i2c_davinci_func(struct i2c_adapter *adap)
{
- return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK);
+ return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
}
static void terminate_read(struct davinci_i2c_dev *dev)
@@ -431,6 +514,14 @@ static irqreturn_t i2c_davinci_isr(int this_irq, void *dev_id)
case DAVINCI_I2C_IVR_ARDY:
davinci_i2c_write_reg(dev,
DAVINCI_I2C_STR_REG, DAVINCI_I2C_STR_ARDY);
+ if (((dev->buf_len == 0) && (dev->stop != 0)) ||
+ (dev->cmd_err & DAVINCI_I2C_STR_NACK)) {
+ w = davinci_i2c_read_reg(dev,
+ DAVINCI_I2C_MDR_REG);
+ w |= DAVINCI_I2C_MDR_STP;
+ davinci_i2c_write_reg(dev,
+ DAVINCI_I2C_MDR_REG, w);
+ }
complete(&dev->cmd_complete);
break;
@@ -462,7 +553,7 @@ static irqreturn_t i2c_davinci_isr(int this_irq, void *dev_id)
w = davinci_i2c_read_reg(dev,
DAVINCI_I2C_IMR_REG);
- MOD_REG_BIT(w, DAVINCI_I2C_IMR_XRDY, 0);
+ w &= ~DAVINCI_I2C_IMR_XRDY;
davinci_i2c_write_reg(dev,
DAVINCI_I2C_IMR_REG,
w);
@@ -491,6 +582,48 @@ static irqreturn_t i2c_davinci_isr(int this_irq, void *dev_id)
return count ? IRQ_HANDLED : IRQ_NONE;
}
+#ifdef CONFIG_CPU_FREQ
+static int i2c_davinci_cpufreq_transition(struct notifier_block *nb,
+ unsigned long val, void *data)
+{
+ struct davinci_i2c_dev *dev;
+
+ dev = container_of(nb, struct davinci_i2c_dev, freq_transition);
+ if (val == CPUFREQ_PRECHANGE) {
+ wait_for_completion(&dev->xfr_complete);
+ davinci_i2c_reset_ctrl(dev, 0);
+ } else if (val == CPUFREQ_POSTCHANGE) {
+ i2c_davinci_calc_clk_dividers(dev);
+ davinci_i2c_reset_ctrl(dev, 1);
+ }
+
+ return 0;
+}
+
+static inline int i2c_davinci_cpufreq_register(struct davinci_i2c_dev *dev)
+{
+ dev->freq_transition.notifier_call = i2c_davinci_cpufreq_transition;
+
+ return cpufreq_register_notifier(&dev->freq_transition,
+ CPUFREQ_TRANSITION_NOTIFIER);
+}
+
+static inline void i2c_davinci_cpufreq_deregister(struct davinci_i2c_dev *dev)
+{
+ cpufreq_unregister_notifier(&dev->freq_transition,
+ CPUFREQ_TRANSITION_NOTIFIER);
+}
+#else
+static inline int i2c_davinci_cpufreq_register(struct davinci_i2c_dev *dev)
+{
+ return 0;
+}
+
+static inline void i2c_davinci_cpufreq_deregister(struct davinci_i2c_dev *dev)
+{
+}
+#endif
+
static struct i2c_algorithm i2c_davinci_algo = {
.master_xfer = i2c_davinci_xfer,
.functionality = i2c_davinci_func,
@@ -530,6 +663,9 @@ static int davinci_i2c_probe(struct platform_device *pdev)
}
init_completion(&dev->cmd_complete);
+#ifdef CONFIG_CPU_FREQ
+ init_completion(&dev->xfr_complete);
+#endif
dev->dev = get_device(&pdev->dev);
dev->irq = irq->start;
platform_set_drvdata(pdev, dev);
@@ -541,7 +677,12 @@ static int davinci_i2c_probe(struct platform_device *pdev)
}
clk_enable(dev->clk);
- dev->base = (void __iomem *)IO_ADDRESS(mem->start);
+ dev->base = ioremap(mem->start, resource_size(mem));
+ if (!dev->base) {
+ r = -EBUSY;
+ goto err_mem_ioremap;
+ }
+
i2c_davinci_init(dev);
r = request_irq(dev->irq, i2c_davinci_isr, 0, pdev->name, dev);
@@ -550,6 +691,12 @@ static int davinci_i2c_probe(struct platform_device *pdev)
goto err_unuse_clocks;
}
+ r = i2c_davinci_cpufreq_register(dev);
+ if (r) {
+ dev_err(&pdev->dev, "failed to register cpufreq\n");
+ goto err_free_irq;
+ }
+
adap = &dev->adapter;
i2c_set_adapdata(adap, dev);
adap->owner = THIS_MODULE;
@@ -571,6 +718,8 @@ static int davinci_i2c_probe(struct platform_device *pdev)
err_free_irq:
free_irq(dev->irq, dev);
err_unuse_clocks:
+ iounmap(dev->base);
+err_mem_ioremap:
clk_disable(dev->clk);
clk_put(dev->clk);
dev->clk = NULL;
@@ -589,6 +738,8 @@ static int davinci_i2c_remove(struct platform_device *pdev)
struct davinci_i2c_dev *dev = platform_get_drvdata(pdev);
struct resource *mem;
+ i2c_davinci_cpufreq_deregister(dev);
+
platform_set_drvdata(pdev, NULL);
i2c_del_adapter(&dev->adapter);
put_device(&pdev->dev);
@@ -599,6 +750,7 @@ static int davinci_i2c_remove(struct platform_device *pdev)
davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, 0);
free_irq(IRQ_I2C, dev);
+ iounmap(dev->base);
kfree(dev);
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@@ -606,6 +758,41 @@ static int davinci_i2c_remove(struct platform_device *pdev)
return 0;
}
+#ifdef CONFIG_PM
+static int davinci_i2c_suspend(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct davinci_i2c_dev *i2c_dev = platform_get_drvdata(pdev);
+
+ /* put I2C into reset */
+ davinci_i2c_reset_ctrl(i2c_dev, 0);
+ clk_disable(i2c_dev->clk);
+
+ return 0;
+}
+
+static int davinci_i2c_resume(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct davinci_i2c_dev *i2c_dev = platform_get_drvdata(pdev);
+
+ clk_enable(i2c_dev->clk);
+ /* take I2C out of reset */
+ davinci_i2c_reset_ctrl(i2c_dev, 1);
+
+ return 0;
+}
+
+static const struct dev_pm_ops davinci_i2c_pm = {
+ .suspend = davinci_i2c_suspend,
+ .resume = davinci_i2c_resume,
+};
+
+#define davinci_i2c_pm_ops (&davinci_i2c_pm)
+#else
+#define davinci_i2c_pm_ops NULL
+#endif
+
/* work with hotplug and coldplug */
MODULE_ALIAS("platform:i2c_davinci");
@@ -615,6 +802,7 @@ static struct platform_driver davinci_i2c_driver = {
.driver = {
.name = "i2c_davinci",
.owner = THIS_MODULE,
+ .pm = davinci_i2c_pm_ops,
},
};
diff --git a/drivers/i2c/busses/i2c-ibm_iic.c b/drivers/i2c/busses/i2c-ibm_iic.c
index bf34413..43ca32f 100644
--- a/drivers/i2c/busses/i2c-ibm_iic.c
+++ b/drivers/i2c/busses/i2c-ibm_iic.c
@@ -661,7 +661,7 @@ static inline u8 iic_clckdiv(unsigned int opb)
return (u8)((opb + 9) / 10 - 1);
}
-static int __devinit iic_request_irq(struct of_device *ofdev,
+static int __devinit iic_request_irq(struct platform_device *ofdev,
struct ibm_iic_private *dev)
{
struct device_node *np = ofdev->dev.of_node;
@@ -692,7 +692,7 @@ static int __devinit iic_request_irq(struct of_device *ofdev,
/*
* Register single IIC interface
*/
-static int __devinit iic_probe(struct of_device *ofdev,
+static int __devinit iic_probe(struct platform_device *ofdev,
const struct of_device_id *match)
{
struct device_node *np = ofdev->dev.of_node;
@@ -745,6 +745,7 @@ static int __devinit iic_probe(struct of_device *ofdev,
/* Register it with i2c layer */
adap = &dev->adap;
adap->dev.parent = &ofdev->dev;
+ adap->dev.of_node = of_node_get(np);
strlcpy(adap->name, "IBM IIC", sizeof(adap->name));
i2c_set_adapdata(adap, dev);
adap->class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
@@ -760,9 +761,6 @@ static int __devinit iic_probe(struct of_device *ofdev,
dev_info(&ofdev->dev, "using %s mode\n",
dev->fast_mode ? "fast (400 kHz)" : "standard (100 kHz)");
- /* Now register all the child nodes */
- of_register_i2c_devices(adap, np);
-
return 0;
error_cleanup:
@@ -782,7 +780,7 @@ error_cleanup:
/*
* Cleanup initialized IIC interface
*/
-static int __devexit iic_remove(struct of_device *ofdev)
+static int __devexit iic_remove(struct platform_device *ofdev)
{
struct ibm_iic_private *dev = dev_get_drvdata(&ofdev->dev);
diff --git a/drivers/i2c/busses/i2c-mpc.c b/drivers/i2c/busses/i2c-mpc.c
index df00eb1..a1c419a 100644
--- a/drivers/i2c/busses/i2c-mpc.c
+++ b/drivers/i2c/busses/i2c-mpc.c
@@ -63,6 +63,7 @@ struct mpc_i2c {
wait_queue_head_t queue;
struct i2c_adapter adap;
int irq;
+ u32 real_clk;
};
struct mpc_i2c_divider {
@@ -96,20 +97,23 @@ static irqreturn_t mpc_i2c_isr(int irq, void *dev_id)
/* Sometimes 9th clock pulse isn't generated, and slave doesn't release
* the bus, because it wants to send ACK.
* Following sequence of enabling/disabling and sending start/stop generates
- * the pulse, so it's all OK.
+ * the 9 pulses, so it's all OK.
*/
static void mpc_i2c_fixup(struct mpc_i2c *i2c)
{
- writeccr(i2c, 0);
- udelay(30);
- writeccr(i2c, CCR_MEN);
- udelay(30);
- writeccr(i2c, CCR_MSTA | CCR_MTX);
- udelay(30);
- writeccr(i2c, CCR_MSTA | CCR_MTX | CCR_MEN);
- udelay(30);
- writeccr(i2c, CCR_MEN);
- udelay(30);
+ int k;
+ u32 delay_val = 1000000 / i2c->real_clk + 1;
+
+ if (delay_val < 2)
+ delay_val = 2;
+
+ for (k = 9; k; k--) {
+ writeccr(i2c, 0);
+ writeccr(i2c, CCR_MSTA | CCR_MTX | CCR_MEN);
+ udelay(delay_val);
+ writeccr(i2c, CCR_MEN);
+ udelay(delay_val << 1);
+ }
}
static int i2c_wait(struct mpc_i2c *i2c, unsigned timeout, int writing)
@@ -190,15 +194,18 @@ static const struct mpc_i2c_divider mpc_i2c_dividers_52xx[] __devinitconst = {
};
static int __devinit mpc_i2c_get_fdr_52xx(struct device_node *node, u32 clock,
- int prescaler)
+ int prescaler, u32 *real_clk)
{
const struct mpc_i2c_divider *div = NULL;
unsigned int pvr = mfspr(SPRN_PVR);
u32 divider;
int i;
- if (clock == MPC_I2C_CLOCK_LEGACY)
+ if (clock == MPC_I2C_CLOCK_LEGACY) {
+ /* see below - default fdr = 0x3f -> div = 2048 */
+ *real_clk = mpc5xxx_get_bus_frequency(node) / 2048;
return -EINVAL;
+ }
/* Determine divider value */
divider = mpc5xxx_get_bus_frequency(node) / clock;
@@ -216,7 +223,8 @@ static int __devinit mpc_i2c_get_fdr_52xx(struct device_node *node, u32 clock,
break;
}
- return div ? (int)div->fdr : -EINVAL;
+ *real_clk = mpc5xxx_get_bus_frequency(node) / div->divider;
+ return (int)div->fdr;
}
static void __devinit mpc_i2c_setup_52xx(struct device_node *node,
@@ -231,13 +239,14 @@ static void __devinit mpc_i2c_setup_52xx(struct device_node *node,
return;
}
- ret = mpc_i2c_get_fdr_52xx(node, clock, prescaler);
+ ret = mpc_i2c_get_fdr_52xx(node, clock, prescaler, &i2c->real_clk);
fdr = (ret >= 0) ? ret : 0x3f; /* backward compatibility */
writeb(fdr & 0xff, i2c->base + MPC_I2C_FDR);
if (ret >= 0)
- dev_info(i2c->dev, "clock %d Hz (fdr=%d)\n", clock, fdr);
+ dev_info(i2c->dev, "clock %u Hz (fdr=%d)\n", i2c->real_clk,
+ fdr);
}
#else /* !(CONFIG_PPC_MPC52xx || CONFIG_PPC_MPC512x) */
static void __devinit mpc_i2c_setup_52xx(struct device_node *node,
@@ -334,14 +343,17 @@ static u32 __devinit mpc_i2c_get_sec_cfg_8xxx(void)
}
static int __devinit mpc_i2c_get_fdr_8xxx(struct device_node *node, u32 clock,
- u32 prescaler)
+ u32 prescaler, u32 *real_clk)
{
const struct mpc_i2c_divider *div = NULL;
u32 divider;
int i;
- if (clock == MPC_I2C_CLOCK_LEGACY)
+ if (clock == MPC_I2C_CLOCK_LEGACY) {
+ /* see below - default fdr = 0x1031 -> div = 16 * 3072 */
+ *real_clk = fsl_get_sys_freq() / prescaler / (16 * 3072);
return -EINVAL;
+ }
/* Determine proper divider value */
if (of_device_is_compatible(node, "fsl,mpc8544-i2c"))
@@ -364,6 +376,7 @@ static int __devinit mpc_i2c_get_fdr_8xxx(struct device_node *node, u32 clock,
break;
}
+ *real_clk = fsl_get_sys_freq() / prescaler / div->divider;
return div ? (int)div->fdr : -EINVAL;
}
@@ -380,7 +393,7 @@ static void __devinit mpc_i2c_setup_8xxx(struct device_node *node,
return;
}
- ret = mpc_i2c_get_fdr_8xxx(node, clock, prescaler);
+ ret = mpc_i2c_get_fdr_8xxx(node, clock, prescaler, &i2c->real_clk);
fdr = (ret >= 0) ? ret : 0x1031; /* backward compatibility */
writeb(fdr & 0xff, i2c->base + MPC_I2C_FDR);
@@ -388,7 +401,7 @@ static void __devinit mpc_i2c_setup_8xxx(struct device_node *node,
if (ret >= 0)
dev_info(i2c->dev, "clock %d Hz (dfsrr=%d fdr=%d)\n",
- clock, fdr >> 8, fdr & 0xff);
+ i2c->real_clk, fdr >> 8, fdr & 0xff);
}
#else /* !CONFIG_FSL_SOC */
@@ -500,10 +513,14 @@ static int mpc_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
return -EINTR;
}
if (time_after(jiffies, orig_jiffies + HZ)) {
+ u8 status = readb(i2c->base + MPC_I2C_SR);
+
dev_dbg(i2c->dev, "timeout\n");
- if (readb(i2c->base + MPC_I2C_SR) ==
- (CSR_MCF | CSR_MBB | CSR_RXAK))
+ if ((status & (CSR_MCF | CSR_MBB | CSR_RXAK)) != 0) {
+ writeb(status & ~CSR_MAL,
+ i2c->base + MPC_I2C_SR);
mpc_i2c_fixup(i2c);
+ }
return -EIO;
}
schedule();
@@ -543,7 +560,7 @@ static struct i2c_adapter mpc_ops = {
.timeout = HZ,
};
-static int __devinit fsl_i2c_probe(struct of_device *op,
+static int __devinit fsl_i2c_probe(struct platform_device *op,
const struct of_device_id *match)
{
struct mpc_i2c *i2c;
@@ -595,18 +612,26 @@ static int __devinit fsl_i2c_probe(struct of_device *op,
mpc_i2c_setup_8xxx(op->dev.of_node, i2c, clock, 0);
}
+ prop = of_get_property(op->dev.of_node, "fsl,timeout", &plen);
+ if (prop && plen == sizeof(u32)) {
+ mpc_ops.timeout = *prop * HZ / 1000000;
+ if (mpc_ops.timeout < 5)
+ mpc_ops.timeout = 5;
+ }
+ dev_info(i2c->dev, "timeout %u us\n", mpc_ops.timeout * 1000000 / HZ);
+
dev_set_drvdata(&op->dev, i2c);
i2c->adap = mpc_ops;
i2c_set_adapdata(&i2c->adap, i2c);
i2c->adap.dev.parent = &op->dev;
+ i2c->adap.dev.of_node = of_node_get(op->dev.of_node);
result = i2c_add_adapter(&i2c->adap);
if (result < 0) {
dev_err(i2c->dev, "failed to add adapter\n");
goto fail_add;
}
- of_register_i2c_devices(&i2c->adap, op->dev.of_node);
return result;
@@ -621,7 +646,7 @@ static int __devinit fsl_i2c_probe(struct of_device *op,
return result;
};
-static int __devexit fsl_i2c_remove(struct of_device *op)
+static int __devexit fsl_i2c_remove(struct platform_device *op)
{
struct mpc_i2c *i2c = dev_get_drvdata(&op->dev);
diff --git a/drivers/i2c/busses/i2c-nuc900.c b/drivers/i2c/busses/i2c-nuc900.c
new file mode 100644
index 0000000..92d770d
--- /dev/null
+++ b/drivers/i2c/busses/i2c-nuc900.c
@@ -0,0 +1,709 @@
+/*
+ * linux/drivers/i2c/busses/i2c-nuc900.c
+ *
+ * Copyright (c) 2010 Nuvoton technology corporation.
+ *
+ * This driver based on S3C2410 I2C driver of Ben Dooks <ben-Y5A6D6n0/KfQXOPxS62xeg@public.gmane.org>.
+ * Written by Wan ZongShun <mcuos.com-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation;version 2 of the License.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+
+#include <linux/i2c.h>
+#include <linux/i2c-id.h>
+#include <linux/init.h>
+#include <linux/time.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/platform_device.h>
+#include <linux/clk.h>
+#include <linux/cpufreq.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+
+#include <mach/mfp.h>
+#include <mach/i2c.h>
+
+/* nuc900 i2c registers offset */
+
+#define CSR 0x00
+#define DIVIDER 0x04
+#define CMDR 0x08
+#define SWR 0x0C
+#define RXR 0x10
+#define TXR 0x14
+
+/* nuc900 i2c CSR register bits */
+
+#define IRQEN 0x003
+#define I2CBUSY 0x400
+#define I2CSTART 0x018
+#define IRQFLAG 0x004
+#define ARBIT_LOST 0x200
+#define SLAVE_ACK 0x800
+
+/* nuc900 i2c CMDR register bits */
+
+#define I2C_CMD_START 0x10
+#define I2C_CMD_STOP 0x08
+#define I2C_CMD_READ 0x04
+#define I2C_CMD_WRITE 0x02
+#define I2C_CMD_NACK 0x01
+
+/* i2c controller state */
+
+enum nuc900_i2c_state {
+ STATE_IDLE,
+ STATE_START,
+ STATE_READ,
+ STATE_WRITE,
+ STATE_STOP
+};
+
+/* i2c controller private data */
+
+struct nuc900_i2c {
+ spinlock_t lock;
+ wait_queue_head_t wait;
+
+ struct i2c_msg *msg;
+ unsigned int msg_num;
+ unsigned int msg_idx;
+ unsigned int msg_ptr;
+ unsigned int irq;
+
+ enum nuc900_i2c_state state;
+
+ void __iomem *regs;
+ struct clk *clk;
+ struct device *dev;
+ struct resource *ioarea;
+ struct i2c_adapter adap;
+};
+
+/* nuc900_i2c_master_complete
+ *
+ * complete the message and wake up the caller, using the given return code,
+ * or zero to mean ok.
+*/
+
+static inline void nuc900_i2c_master_complete(struct nuc900_i2c *i2c, int ret)
+{
+ dev_dbg(i2c->dev, "master_complete %d\n", ret);
+
+ i2c->msg_ptr = 0;
+ i2c->msg = NULL;
+ i2c->msg_idx++;
+ i2c->msg_num = 0;
+ if (ret)
+ i2c->msg_idx = ret;
+
+ wake_up(&i2c->wait);
+}
+
+/* irq enable/disable functions */
+
+static inline void nuc900_i2c_disable_irq(struct nuc900_i2c *i2c)
+{
+ unsigned long tmp;
+
+ tmp = readl(i2c->regs + CSR);
+ writel(tmp & ~IRQEN, i2c->regs + CSR);
+}
+
+static inline void nuc900_i2c_enable_irq(struct nuc900_i2c *i2c)
+{
+ unsigned long tmp;
+
+ tmp = readl(i2c->regs + CSR);
+ writel(tmp | IRQEN, i2c->regs + CSR);
+}
+
+
+/* nuc900_i2c_message_start
+ *
+ * put the start of a message onto the bus
+*/
+
+static void nuc900_i2c_message_start(struct nuc900_i2c *i2c,
+ struct i2c_msg *msg)
+{
+ unsigned int addr = (msg->addr & 0x7f) << 1;
+
+ if (msg->flags & I2C_M_RD)
+ addr |= 0x1;
+ writel(addr & 0xff, i2c->regs + TXR);
+ writel(I2C_CMD_START | I2C_CMD_WRITE, i2c->regs + CMDR);
+}
+
+static inline void nuc900_i2c_stop(struct nuc900_i2c *i2c, int ret)
+{
+
+ dev_dbg(i2c->dev, "STOP\n");
+
+ /* stop the transfer */
+ i2c->state = STATE_STOP;
+ writel(I2C_CMD_STOP, i2c->regs + CMDR);
+
+ nuc900_i2c_master_complete(i2c, ret);
+ nuc900_i2c_disable_irq(i2c);
+}
+
+/* helper functions to determine the current state in the set of
+ * messages we are sending
+*/
+
+/* is_lastmsg()
+ *
+ * returns TRUE if the current message is the last in the set
+*/
+
+static inline int is_lastmsg(struct nuc900_i2c *i2c)
+{
+ return i2c->msg_idx >= (i2c->msg_num - 1);
+}
+
+/* is_msglast
+ *
+ * returns TRUE if we this is the last byte in the current message
+*/
+
+static inline int is_msglast(struct nuc900_i2c *i2c)
+{
+ return i2c->msg_ptr == i2c->msg->len-1;
+}
+
+/* is_msgend
+ *
+ * returns TRUE if we reached the end of the current message
+*/
+
+static inline int is_msgend(struct nuc900_i2c *i2c)
+{
+ return i2c->msg_ptr >= i2c->msg->len;
+}
+
+/* i2c_nuc900_irq_nextbyte
+ *
+ * process an interrupt and work out what to do
+ */
+
+static void i2c_nuc900_irq_nextbyte(struct nuc900_i2c *i2c,
+ unsigned long iicstat)
+{
+ unsigned char byte;
+
+ switch (i2c->state) {
+
+ case STATE_IDLE:
+ dev_err(i2c->dev, "%s: called in STATE_IDLE\n", __func__);
+ break;
+
+ case STATE_STOP:
+ dev_err(i2c->dev, "%s: called in STATE_STOP\n", __func__);
+ nuc900_i2c_disable_irq(i2c);
+ break;
+
+ case STATE_START:
+ /* last thing we did was send a start condition on the
+ * bus, or started a new i2c message
+ */
+
+ if (iicstat & SLAVE_ACK &&
+ !(i2c->msg->flags & I2C_M_IGNORE_NAK)) {
+ /* ack was not received... */
+
+ dev_dbg(i2c->dev, "ack was not received\n");
+ nuc900_i2c_stop(i2c, -ENXIO);
+ break;
+ }
+
+ if (i2c->msg->flags & I2C_M_RD)
+ i2c->state = STATE_READ;
+ else
+ i2c->state = STATE_WRITE;
+
+ /* terminate the transfer if there is nothing to do
+ * as this is used by the i2c probe to find devices.
+ */
+
+ if (is_lastmsg(i2c) && i2c->msg->len == 0) {
+ nuc900_i2c_stop(i2c, 0);
+ break;
+ }
+
+ if (i2c->state == STATE_READ)
+ goto prepare_read;
+
+ /* fall through to the write state, as we will need to
+ * send a byte as well
+ */
+
+ case STATE_WRITE:
+ /* we are writing data to the device... check for the
+ * end of the message, and if so, work out what to do
+ */
+
+ if (!(i2c->msg->flags & I2C_M_IGNORE_NAK)) {
+ if (iicstat & SLAVE_ACK) {
+ dev_dbg(i2c->dev, "WRITE: No Ack\n");
+
+ nuc900_i2c_stop(i2c, -ECONNREFUSED);
+ break;
+ }
+ }
+
+retry_write:
+
+ if (!is_msgend(i2c)) {
+ byte = i2c->msg->buf[i2c->msg_ptr++];
+ writeb(byte, i2c->regs + TXR);
+ writel(I2C_CMD_WRITE, i2c->regs + CMDR);
+
+ } else if (!is_lastmsg(i2c)) {
+ /* we need to go to the next i2c message */
+
+ dev_dbg(i2c->dev, "WRITE: Next Message\n");
+
+ i2c->msg_ptr = 0;
+ i2c->msg_idx++;
+ i2c->msg++;
+
+ /* check to see if we need to do another message */
+ if (i2c->msg->flags & I2C_M_NOSTART) {
+
+ if (i2c->msg->flags & I2C_M_RD) {
+ /* cannot do this, the controller
+ * forces us to send a new START
+ * when we change direction
+ */
+
+ nuc900_i2c_stop(i2c, -EINVAL);
+ }
+
+ goto retry_write;
+ } else {
+ /* send the new start */
+ nuc900_i2c_message_start(i2c, i2c->msg);
+ i2c->state = STATE_START;
+ }
+
+ } else {
+ /* send stop */
+
+ nuc900_i2c_stop(i2c, 0);
+ }
+ break;
+
+ case STATE_READ:
+ /* we have a byte of data in the data register, do
+ * something with it, and then work out wether we are
+ * going to do any more read/write
+ */
+
+ byte = readb(i2c->regs + RXR);
+ i2c->msg->buf[i2c->msg_ptr++] = byte;
+
+prepare_read:
+ if (is_msglast(i2c)) {
+ /* last byte of buffer */
+
+ if (is_lastmsg(i2c))
+ writel(I2C_CMD_READ | I2C_CMD_NACK,
+ i2c->regs + CMDR);
+
+ } else if (is_msgend(i2c)) {
+ /* ok, we've read the entire buffer, see if there
+ * is anything else we need to do
+ */
+
+ if (is_lastmsg(i2c)) {
+ /* last message, send stop and complete */
+ dev_dbg(i2c->dev, "READ: Send Stop\n");
+
+ nuc900_i2c_stop(i2c, 0);
+ } else {
+ /* go to the next transfer */
+ dev_dbg(i2c->dev, "READ: Next Transfer\n");
+
+ i2c->msg_ptr = 0;
+ i2c->msg_idx++;
+ i2c->msg++;
+
+ writel(I2C_CMD_READ, i2c->regs + CMDR);
+ }
+
+ } else {
+ writel(I2C_CMD_READ, i2c->regs + CMDR);
+ }
+
+ break;
+ }
+}
+
+/* nuc900_i2c_irq
+ *
+ * top level IRQ servicing routine
+*/
+
+static irqreturn_t nuc900_i2c_irq(int irqno, void *dev_id)
+{
+ struct nuc900_i2c *i2c = dev_id;
+ unsigned long status;
+
+ status = readl(i2c->regs + CSR);
+ writel(status | IRQFLAG, i2c->regs + CSR);
+
+ if (status & ARBIT_LOST) {
+ /* deal with arbitration loss */
+ dev_err(i2c->dev, "deal with arbitration loss\n");
+ goto out;
+ }
+
+ if (i2c->state == STATE_IDLE) {
+ dev_dbg(i2c->dev, "IRQ: error i2c->state == IDLE\n");
+ goto out;
+ }
+
+ /* pretty much this leaves us with the fact that we've
+ * transmitted or received whatever byte we last sent
+ */
+
+ i2c_nuc900_irq_nextbyte(i2c, status);
+
+ out:
+ return IRQ_HANDLED;
+}
+
+
+/* nuc900_i2c_set_master
+ *
+ * get the i2c bus for a master transaction
+*/
+
+static int nuc900_i2c_set_master(struct nuc900_i2c *i2c)
+{
+ int timeout = 400;
+
+ while (timeout-- > 0) {
+ if (((readl(i2c->regs + SWR) & I2CSTART) == I2CSTART) &&
+ ((readl(i2c->regs + CSR) & I2CBUSY) == 0)) {
+ return 0;
+ }
+
+ msleep(1);
+ }
+
+ return -ETIMEDOUT;
+}
+
+/* nuc900_i2c_doxfer
+ *
+ * this starts an i2c transfer
+*/
+
+static int nuc900_i2c_doxfer(struct nuc900_i2c *i2c,
+ struct i2c_msg *msgs, int num)
+{
+ unsigned long iicstat, timeout;
+ int spins = 20;
+ int ret;
+
+ ret = nuc900_i2c_set_master(i2c);
+ if (ret != 0) {
+ dev_err(i2c->dev, "cannot get bus (error %d)\n", ret);
+ ret = -EAGAIN;
+ goto out;
+ }
+
+ spin_lock_irq(&i2c->lock);
+
+ i2c->msg = msgs;
+ i2c->msg_num = num;
+ i2c->msg_ptr = 0;
+ i2c->msg_idx = 0;
+ i2c->state = STATE_START;
+
+ nuc900_i2c_message_start(i2c, msgs);
+ spin_unlock_irq(&i2c->lock);
+
+ timeout = wait_event_timeout(i2c->wait, i2c->msg_num == 0, HZ * 5);
+
+ ret = i2c->msg_idx;
+
+ /* having these next two as dev_err() makes life very
+ * noisy when doing an i2cdetect
+ */
+
+ if (timeout == 0)
+ dev_dbg(i2c->dev, "timeout\n");
+ else if (ret != num)
+ dev_dbg(i2c->dev, "incomplete xfer (%d)\n", ret);
+
+ /* ensure the stop has been through the bus */
+
+ dev_dbg(i2c->dev, "waiting for bus idle\n");
+
+ /* first, try busy waiting briefly */
+ do {
+ iicstat = readl(i2c->regs + CSR);
+ } while ((iicstat & I2CBUSY) && --spins);
+
+ /* if that timed out sleep */
+ if (!spins) {
+ msleep(1);
+ iicstat = readl(i2c->regs + CSR);
+ }
+
+ if (iicstat & I2CBUSY)
+ dev_warn(i2c->dev, "timeout waiting for bus idle\n");
+
+ out:
+ return ret;
+}
+
+/* nuc900_i2c_xfer
+ *
+ * first port of call from the i2c bus code when an message needs
+ * transferring across the i2c bus.
+*/
+
+static int nuc900_i2c_xfer(struct i2c_adapter *adap,
+ struct i2c_msg *msgs, int num)
+{
+ struct nuc900_i2c *i2c = (struct nuc900_i2c *)adap->algo_data;
+ int retry;
+ int ret;
+
+ nuc900_i2c_enable_irq(i2c);
+
+ for (retry = 0; retry < adap->retries; retry++) {
+
+ ret = nuc900_i2c_doxfer(i2c, msgs, num);
+
+ if (ret != -EAGAIN)
+ return ret;
+
+ dev_dbg(i2c->dev, "Retrying transmission (%d)\n", retry);
+
+ udelay(100);
+ }
+
+ return -EREMOTEIO;
+}
+
+/* declare our i2c functionality */
+static u32 nuc900_i2c_func(struct i2c_adapter *adap)
+{
+ return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_PROTOCOL_MANGLING;
+}
+
+/* i2c bus registration info */
+
+static const struct i2c_algorithm nuc900_i2c_algorithm = {
+ .master_xfer = nuc900_i2c_xfer,
+ .functionality = nuc900_i2c_func,
+};
+
+/* nuc900_i2c_probe
+ *
+ * called by the bus driver when a suitable device is found
+*/
+
+static int __devinit nuc900_i2c_probe(struct platform_device *pdev)
+{
+ struct nuc900_i2c *i2c;
+ struct nuc900_platform_i2c *pdata;
+ struct resource *res;
+ int ret;
+
+ pdata = pdev->dev.platform_data;
+ if (!pdata) {
+ dev_err(&pdev->dev, "no platform data\n");
+ return -EINVAL;
+ }
+
+ i2c = kzalloc(sizeof(struct nuc900_i2c), GFP_KERNEL);
+ if (!i2c) {
+ dev_err(&pdev->dev, "no memory for state\n");
+ return -ENOMEM;
+ }
+
+ strlcpy(i2c->adap.name, "nuc900-i2c0", sizeof(i2c->adap.name));
+ i2c->adap.owner = THIS_MODULE;
+ i2c->adap.algo = &nuc900_i2c_algorithm;
+ i2c->adap.retries = 2;
+ i2c->adap.class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
+
+ spin_lock_init(&i2c->lock);
+ init_waitqueue_head(&i2c->wait);
+
+ /* find the clock and enable it */
+
+ i2c->dev = &pdev->dev;
+ i2c->clk = clk_get(&pdev->dev, NULL);
+ if (IS_ERR(i2c->clk)) {
+ dev_err(&pdev->dev, "cannot get clock\n");
+ ret = -ENOENT;
+ goto err_noclk;
+ }
+
+ dev_dbg(&pdev->dev, "clock source %p\n", i2c->clk);
+
+ clk_enable(i2c->clk);
+
+ /* map the registers */
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (res == NULL) {
+ dev_err(&pdev->dev, "cannot find IO resource\n");
+ ret = -ENOENT;
+ goto err_clk;
+ }
+
+ i2c->ioarea = request_mem_region(res->start, resource_size(res),
+ pdev->name);
+
+ if (i2c->ioarea == NULL) {
+ dev_err(&pdev->dev, "cannot request IO\n");
+ ret = -ENXIO;
+ goto err_clk;
+ }
+
+ i2c->regs = ioremap(res->start, resource_size(res));
+
+ if (i2c->regs == NULL) {
+ dev_err(&pdev->dev, "cannot map IO\n");
+ ret = -ENXIO;
+ goto err_ioarea;
+ }
+
+ dev_dbg(&pdev->dev, "registers %p (%p, %p)\n",
+ i2c->regs, i2c->ioarea, res);
+
+ /* setup info block for the i2c core */
+
+ i2c->adap.algo_data = i2c;
+ i2c->adap.dev.parent = &pdev->dev;
+
+ mfp_set_groupg(&pdev->dev);
+
+ clk_get_rate(i2c->clk);
+
+ ret = (i2c->clk.apbfreq)/(pdata->bus_freq * 5) - 1;
+ writel(ret & 0xffff, i2c->regs + DIVIDER);
+
+ /* find the IRQ for this unit (note, this relies on the init call to
+ * ensure no current IRQs pending
+ */
+
+ i2c->irq = ret = platform_get_irq(pdev, 0);
+ if (ret <= 0) {
+ dev_err(&pdev->dev, "cannot find IRQ\n");
+ goto err_iomap;
+ }
+
+ ret = request_irq(i2c->irq, nuc900_i2c_irq, IRQF_DISABLED | IRQF_SHARED,
+ dev_name(&pdev->dev), i2c);
+
+ if (ret != 0) {
+ dev_err(&pdev->dev, "cannot claim IRQ %d\n", i2c->irq);
+ goto err_iomap;
+ }
+
+ /* Note, previous versions of the driver used i2c_add_adapter()
+ * to add the bus at any number. We now pass the bus number via
+ * the platform data, so if unset it will now default to always
+ * being bus 0.
+ */
+
+ i2c->adap.nr = pdata->bus_num;
+
+ ret = i2c_add_numbered_adapter(&i2c->adap);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to add bus to i2c core\n");
+ goto err_irq;
+ }
+
+ platform_set_drvdata(pdev, i2c);
+
+ dev_info(&pdev->dev, "%s: NUC900 I2C adapter\n",
+ dev_name(&i2c->adap.dev));
+ return 0;
+
+ err_irq:
+ free_irq(i2c->irq, i2c);
+
+ err_iomap:
+ iounmap(i2c->regs);
+
+ err_ioarea:
+ release_resource(i2c->ioarea);
+ kfree(i2c->ioarea);
+
+ err_clk:
+ clk_disable(i2c->clk);
+ clk_put(i2c->clk);
+
+ err_noclk:
+ kfree(i2c);
+ return ret;
+}
+
+/* nuc900_i2c_remove
+ *
+ * called when device is removed from the bus
+*/
+
+static int __devexit nuc900_i2c_remove(struct platform_device *pdev)
+{
+ struct nuc900_i2c *i2c = platform_get_drvdata(pdev);
+
+ i2c_del_adapter(&i2c->adap);
+ free_irq(i2c->irq, i2c);
+
+ clk_disable(i2c->clk);
+ clk_put(i2c->clk);
+
+ iounmap(i2c->regs);
+
+ release_resource(i2c->ioarea);
+ kfree(i2c->ioarea);
+ kfree(i2c);
+
+ return 0;
+}
+
+static struct platform_driver nuc900_i2c_driver = {
+ .probe = nuc900_i2c_probe,
+ .remove = __devexit_p(nuc900_i2c_remove),
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = "nuc900-i2c0",
+ },
+};
+
+static int __init i2c_adap_nuc900_init(void)
+{
+ return platform_driver_register(&nuc900_i2c_driver);
+}
+
+static void __exit i2c_adap_nuc900_exit(void)
+{
+ platform_driver_unregister(&nuc900_i2c_driver);
+}
+subsys_initcall(i2c_adap_nuc900_init);
+module_exit(i2c_adap_nuc900_exit);
+
+MODULE_DESCRIPTION("NUC900 I2C Bus driver");
+MODULE_AUTHOR("Wan ZongShun, <mcuos.com-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:nuc900-i2c0");
diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c
index 020ff23..c94e51b 100644
--- a/drivers/i2c/busses/i2c-pxa.c
+++ b/drivers/i2c/busses/i2c-pxa.c
@@ -1001,7 +1001,7 @@ static int i2c_pxa_probe(struct platform_device *dev)
struct pxa_i2c *i2c;
struct resource *res;
struct i2c_pxa_platform_data *plat = dev->dev.platform_data;
- struct platform_device_id *id = platform_get_device_id(dev);
+ const struct platform_device_id *id = platform_get_device_id(dev);
int ret;
int irq;
diff --git a/drivers/i2c/busses/i2c-sh_mobile.c b/drivers/i2c/busses/i2c-sh_mobile.c
index 97b84b8..2707f5e 100644
--- a/drivers/i2c/busses/i2c-sh_mobile.c
+++ b/drivers/i2c/busses/i2c-sh_mobile.c
@@ -119,8 +119,10 @@ struct sh_mobile_i2c_data {
struct i2c_adapter adap;
struct clk *clk;
+ u_int8_t icic;
u_int8_t iccl;
u_int8_t icch;
+ u_int8_t flags;
spinlock_t lock;
wait_queue_head_t wait;
@@ -129,15 +131,17 @@ struct sh_mobile_i2c_data {
int sr;
};
+#define IIC_FLAG_HAS_ICIC67 (1 << 0)
+
#define NORMAL_SPEED 100000 /* FAST_SPEED 400000 */
/* Register offsets */
-#define ICDR(pd) (pd->reg + 0x00)
-#define ICCR(pd) (pd->reg + 0x04)
-#define ICSR(pd) (pd->reg + 0x08)
-#define ICIC(pd) (pd->reg + 0x0c)
-#define ICCL(pd) (pd->reg + 0x10)
-#define ICCH(pd) (pd->reg + 0x14)
+#define ICDR 0x00
+#define ICCR 0x04
+#define ICSR 0x08
+#define ICIC 0x0c
+#define ICCL 0x10
+#define ICCH 0x14
/* Register bits */
#define ICCR_ICE 0x80
@@ -155,11 +159,32 @@ struct sh_mobile_i2c_data {
#define ICSR_WAIT 0x02
#define ICSR_DTE 0x01
+#define ICIC_ICCLB8 0x80
+#define ICIC_ICCHB8 0x40
#define ICIC_ALE 0x08
#define ICIC_TACKE 0x04
#define ICIC_WAITE 0x02
#define ICIC_DTEE 0x01
+static void iic_wr(struct sh_mobile_i2c_data *pd, int offs, unsigned char data)
+{
+ if (offs == ICIC)
+ data |= pd->icic;
+
+ iowrite8(data, pd->reg + offs);
+}
+
+static unsigned char iic_rd(struct sh_mobile_i2c_data *pd, int offs)
+{
+ return ioread8(pd->reg + offs);
+}
+
+static void iic_set_clr(struct sh_mobile_i2c_data *pd, int offs,
+ unsigned char set, unsigned char clr)
+{
+ iic_wr(pd, offs, (iic_rd(pd, offs) | set) & ~clr);
+}
+
static void activate_ch(struct sh_mobile_i2c_data *pd)
{
unsigned long i2c_clk;
@@ -187,6 +212,14 @@ static void activate_ch(struct sh_mobile_i2c_data *pd)
else
pd->iccl = (u_int8_t)(num/denom);
+ /* one more bit of ICCL in ICIC */
+ if (pd->flags & IIC_FLAG_HAS_ICIC67) {
+ if ((num/denom) > 0xff)
+ pd->icic |= ICIC_ICCLB8;
+ else
+ pd->icic &= ~ICIC_ICCLB8;
+ }
+
/* Calculate the value for icch. From the data sheet:
icch = (p clock / transfer rate) * (H / (L + H)) */
num = i2c_clk * 4;
@@ -196,25 +229,33 @@ static void activate_ch(struct sh_mobile_i2c_data *pd)
else
pd->icch = (u_int8_t)(num/denom);
+ /* one more bit of ICCH in ICIC */
+ if (pd->flags & IIC_FLAG_HAS_ICIC67) {
+ if ((num/denom) > 0xff)
+ pd->icic |= ICIC_ICCHB8;
+ else
+ pd->icic &= ~ICIC_ICCHB8;
+ }
+
/* Enable channel and configure rx ack */
- iowrite8(ioread8(ICCR(pd)) | ICCR_ICE, ICCR(pd));
+ iic_set_clr(pd, ICCR, ICCR_ICE, 0);
/* Mask all interrupts */
- iowrite8(0, ICIC(pd));
+ iic_wr(pd, ICIC, 0);
/* Set the clock */
- iowrite8(pd->iccl, ICCL(pd));
- iowrite8(pd->icch, ICCH(pd));
+ iic_wr(pd, ICCL, pd->iccl);
+ iic_wr(pd, ICCH, pd->icch);
}
static void deactivate_ch(struct sh_mobile_i2c_data *pd)
{
/* Clear/disable interrupts */
- iowrite8(0, ICSR(pd));
- iowrite8(0, ICIC(pd));
+ iic_wr(pd, ICSR, 0);
+ iic_wr(pd, ICIC, 0);
/* Disable channel */
- iowrite8(ioread8(ICCR(pd)) & ~ICCR_ICE, ICCR(pd));
+ iic_set_clr(pd, ICCR, 0, ICCR_ICE);
/* Disable clock and mark device as idle */
clk_disable(pd->clk);
@@ -233,35 +274,35 @@ static unsigned char i2c_op(struct sh_mobile_i2c_data *pd,
switch (op) {
case OP_START: /* issue start and trigger DTE interrupt */
- iowrite8(0x94, ICCR(pd));
+ iic_wr(pd, ICCR, 0x94);
break;
case OP_TX_FIRST: /* disable DTE interrupt and write data */
- iowrite8(ICIC_WAITE | ICIC_ALE | ICIC_TACKE, ICIC(pd));
- iowrite8(data, ICDR(pd));
+ iic_wr(pd, ICIC, ICIC_WAITE | ICIC_ALE | ICIC_TACKE);
+ iic_wr(pd, ICDR, data);
break;
case OP_TX: /* write data */
- iowrite8(data, ICDR(pd));
+ iic_wr(pd, ICDR, data);
break;
case OP_TX_STOP: /* write data and issue a stop afterwards */
- iowrite8(data, ICDR(pd));
- iowrite8(0x90, ICCR(pd));
+ iic_wr(pd, ICDR, data);
+ iic_wr(pd, ICCR, 0x90);
break;
case OP_TX_TO_RX: /* select read mode */
- iowrite8(0x81, ICCR(pd));
+ iic_wr(pd, ICCR, 0x81);
break;
case OP_RX: /* just read data */
- ret = ioread8(ICDR(pd));
+ ret = iic_rd(pd, ICDR);
break;
case OP_RX_STOP: /* enable DTE interrupt, issue stop */
- iowrite8(ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE,
- ICIC(pd));
- iowrite8(0xc0, ICCR(pd));
+ iic_wr(pd, ICIC,
+ ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE);
+ iic_wr(pd, ICCR, 0xc0);
break;
case OP_RX_STOP_DATA: /* enable DTE interrupt, read data, issue stop */
- iowrite8(ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE,
- ICIC(pd));
- ret = ioread8(ICDR(pd));
- iowrite8(0xc0, ICCR(pd));
+ iic_wr(pd, ICIC,
+ ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE);
+ ret = iic_rd(pd, ICDR);
+ iic_wr(pd, ICCR, 0xc0);
break;
}
@@ -367,7 +408,7 @@ static irqreturn_t sh_mobile_i2c_isr(int irq, void *dev_id)
unsigned char sr;
int wakeup;
- sr = ioread8(ICSR(pd));
+ sr = iic_rd(pd, ICSR);
pd->sr |= sr; /* remember state */
dev_dbg(pd->dev, "i2c_isr 0x%02x 0x%02x %s %d %d!\n", sr, pd->sr,
@@ -376,7 +417,7 @@ static irqreturn_t sh_mobile_i2c_isr(int irq, void *dev_id)
if (sr & (ICSR_AL | ICSR_TACK)) {
/* don't interrupt transaction - continue to issue stop */
- iowrite8(sr & ~(ICSR_AL | ICSR_TACK), ICSR(pd));
+ iic_wr(pd, ICSR, sr & ~(ICSR_AL | ICSR_TACK));
wakeup = 0;
} else if (pd->msg->flags & I2C_M_RD)
wakeup = sh_mobile_i2c_isr_rx(pd);
@@ -384,7 +425,7 @@ static irqreturn_t sh_mobile_i2c_isr(int irq, void *dev_id)
wakeup = sh_mobile_i2c_isr_tx(pd);
if (sr & ICSR_WAIT) /* TODO: add delay here to support slow acks */
- iowrite8(sr & ~ICSR_WAIT, ICSR(pd));
+ iic_wr(pd, ICSR, sr & ~ICSR_WAIT);
if (wakeup) {
pd->sr |= SW_DONE;
@@ -402,21 +443,21 @@ static int start_ch(struct sh_mobile_i2c_data *pd, struct i2c_msg *usr_msg)
}
/* Initialize channel registers */
- iowrite8(ioread8(ICCR(pd)) & ~ICCR_ICE, ICCR(pd));
+ iic_set_clr(pd, ICCR, 0, ICCR_ICE);
/* Enable channel and configure rx ack */
- iowrite8(ioread8(ICCR(pd)) | ICCR_ICE, ICCR(pd));
+ iic_set_clr(pd, ICCR, ICCR_ICE, 0);
/* Set the clock */
- iowrite8(pd->iccl, ICCL(pd));
- iowrite8(pd->icch, ICCH(pd));
+ iic_wr(pd, ICCL, pd->iccl);
+ iic_wr(pd, ICCH, pd->icch);
pd->msg = usr_msg;
pd->pos = -1;
pd->sr = 0;
/* Enable all interrupts to begin with */
- iowrite8(ICIC_WAITE | ICIC_ALE | ICIC_TACKE | ICIC_DTEE, ICIC(pd));
+ iic_wr(pd, ICIC, ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE);
return 0;
}
@@ -451,7 +492,7 @@ static int sh_mobile_i2c_xfer(struct i2c_adapter *adapter,
retry_count = 1000;
again:
- val = ioread8(ICSR(pd));
+ val = iic_rd(pd, ICSR);
dev_dbg(pd->dev, "val 0x%02x pd->sr 0x%02x\n", val, pd->sr);
@@ -579,6 +620,12 @@ static int sh_mobile_i2c_probe(struct platform_device *dev)
goto err_irq;
}
+ /* The IIC blocks on SH-Mobile ARM processors
+ * come with two new bits in ICIC.
+ */
+ if (size > 0x17)
+ pd->flags |= IIC_FLAG_HAS_ICIC67;
+
/* Enable Runtime PM for this device.
*
* Also tell the Runtime PM core to ignore children
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index 0815e10..6649176 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -20,7 +20,9 @@
/* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi>.
All SMBus-related things are written by Frodo Looijaard <frodol@dds.nl>
SMBus 2.0 support by Mark Studebaker <mdsxyz123@yahoo.com> and
- Jean Delvare <khali@linux-fr.org> */
+ Jean Delvare <khali@linux-fr.org>
+ Mux support by Rodolfo Giometti <giometti@enneenne.com> and
+ Michael Lawnick <michael.lawnick.ext@nsn.com> */
#include <linux/module.h>
#include <linux/kernel.h>
@@ -30,6 +32,8 @@
#include <linux/init.h>
#include <linux/idr.h>
#include <linux/mutex.h>
+#include <linux/of_i2c.h>
+#include <linux/of_device.h>
#include <linux/completion.h>
#include <linux/hardirq.h>
#include <linux/irqflags.h>
@@ -70,6 +74,10 @@ static int i2c_device_match(struct device *dev, struct device_driver *drv)
if (!client)
return 0;
+ /* Attempt an OF style match */
+ if (of_driver_match_device(dev, drv))
+ return 1;
+
driver = to_i2c_driver(drv);
/* match on an id table if there is one */
if (driver->id_table)
@@ -417,11 +425,87 @@ static int __i2c_check_addr_busy(struct device *dev, void *addrp)
return 0;
}
+/* walk up mux tree */
+static int i2c_check_mux_parents(struct i2c_adapter *adapter, int addr)
+{
+ int result;
+
+ result = device_for_each_child(&adapter->dev, &addr,
+ __i2c_check_addr_busy);
+
+ if (!result && i2c_parent_is_i2c_adapter(adapter))
+ result = i2c_check_mux_parents(
+ to_i2c_adapter(adapter->dev.parent), addr);
+
+ return result;
+}
+
+/* recurse down mux tree */
+static int i2c_check_mux_children(struct device *dev, void *addrp)
+{
+ int result;
+
+ if (dev->type == &i2c_adapter_type)
+ result = device_for_each_child(dev, addrp,
+ i2c_check_mux_children);
+ else
+ result = __i2c_check_addr_busy(dev, addrp);
+
+ return result;
+}
+
static int i2c_check_addr_busy(struct i2c_adapter *adapter, int addr)
{
- return device_for_each_child(&adapter->dev, &addr,
- __i2c_check_addr_busy);
+ int result = 0;
+
+ if (i2c_parent_is_i2c_adapter(adapter))
+ result = i2c_check_mux_parents(
+ to_i2c_adapter(adapter->dev.parent), addr);
+
+ if (!result)
+ result = device_for_each_child(&adapter->dev, &addr,
+ i2c_check_mux_children);
+
+ return result;
+}
+
+/**
+ * i2c_lock_adapter - Get exclusive access to an I2C bus segment
+ * @adapter: Target I2C bus segment
+ */
+void i2c_lock_adapter(struct i2c_adapter *adapter)
+{
+ if (i2c_parent_is_i2c_adapter(adapter))
+ i2c_lock_adapter(to_i2c_adapter(adapter->dev.parent));
+ else
+ rt_mutex_lock(&adapter->bus_lock);
+}
+EXPORT_SYMBOL_GPL(i2c_lock_adapter);
+
+/**
+ * i2c_trylock_adapter - Try to get exclusive access to an I2C bus segment
+ * @adapter: Target I2C bus segment
+ */
+static int i2c_trylock_adapter(struct i2c_adapter *adapter)
+{
+ if (i2c_parent_is_i2c_adapter(adapter))
+ return i2c_trylock_adapter(to_i2c_adapter(adapter->dev.parent));
+ else
+ return rt_mutex_trylock(&adapter->bus_lock);
+}
+
+/**
+ * i2c_unlock_adapter - Release exclusive access to an I2C bus segment
+ * @adapter: Target I2C bus segment
+ */
+void i2c_unlock_adapter(struct i2c_adapter *adapter)
+{
+ if (i2c_parent_is_i2c_adapter(adapter))
+ i2c_unlock_adapter(to_i2c_adapter(adapter->dev.parent));
+ else
+ rt_mutex_unlock(&adapter->bus_lock);
}
+EXPORT_SYMBOL_GPL(i2c_unlock_adapter);
/**
* i2c_new_device - instantiate an i2c device
@@ -627,9 +711,9 @@ i2c_sysfs_new_device(struct device *dev, struct device_attribute *attr,
return -EINVAL;
/* Keep track of the added device */
- i2c_lock_adapter(adap);
+ mutex_lock(&adap->userspace_clients_lock);
list_add_tail(&client->detected, &adap->userspace_clients);
- i2c_unlock_adapter(adap);
+ mutex_unlock(&adap->userspace_clients_lock);
dev_info(dev, "%s: Instantiated device %s at 0x%02hx\n", "new_device",
info.type, info.addr);
@@ -668,7 +752,7 @@ i2c_sysfs_delete_device(struct device *dev, struct device_attribute *attr,
/* Make sure the device was added through sysfs */
res = -ENOENT;
- i2c_lock_adapter(adap);
+ mutex_lock(&adap->userspace_clients_lock);
list_for_each_entry_safe(client, next, &adap->userspace_clients,
detected) {
if (client->addr == addr) {
@@ -681,7 +765,7 @@ i2c_sysfs_delete_device(struct device *dev, struct device_attribute *attr,
break;
}
}
- i2c_unlock_adapter(adap);
+ mutex_unlock(&adap->userspace_clients_lock);
if (res < 0)
dev_err(dev, "%s: Can't find device in list\n",
@@ -708,10 +792,11 @@ static const struct attribute_group *i2c_adapter_attr_groups[] = {
NULL
};
-static struct device_type i2c_adapter_type = {
+struct device_type i2c_adapter_type = {
.groups = i2c_adapter_attr_groups,
.release = i2c_adapter_dev_release,
};
+EXPORT_SYMBOL_GPL(i2c_adapter_type);
#ifdef CONFIG_I2C_COMPAT
static struct class_compat *i2c_adapter_compat_class;
@@ -754,7 +839,7 @@ static int __process_new_adapter(struct device_driver *d, void *data)
static int i2c_register_adapter(struct i2c_adapter *adap)
{
- int res = 0, dummy;
+ int res = 0;
/* Can't register until after driver model init */
if (unlikely(WARN_ON(!i2c_bus_type.p))) {
@@ -763,6 +848,7 @@ static int i2c_register_adapter(struct i2c_adapter *adap)
}
rt_mutex_init(&adap->bus_lock);
+ mutex_init(&adap->userspace_clients_lock);
INIT_LIST_HEAD(&adap->userspace_clients);
/* Set default timeout to 1 second if not already set */
@@ -790,10 +876,12 @@ static int i2c_register_adapter(struct i2c_adapter *adap)
if (adap->nr < __i2c_first_dynamic_bus_num)
i2c_scan_static_board_info(adap);
+ /* Register devices from the device tree */
+ of_i2c_register_devices(adap);
+
/* Notify drivers */
mutex_lock(&core_lock);
- dummy = bus_for_each_drv(&i2c_bus_type, NULL, adap,
- __process_new_adapter);
+ bus_for_each_drv(&i2c_bus_type, NULL, adap, __process_new_adapter);
mutex_unlock(&core_lock);
return 0;
@@ -966,7 +1054,7 @@ int i2c_del_adapter(struct i2c_adapter *adap)
return res;
/* Remove devices instantiated from sysfs */
- i2c_lock_adapter(adap);
+ mutex_lock(&adap->userspace_clients_lock);
list_for_each_entry_safe(client, next, &adap->userspace_clients,
detected) {
dev_dbg(&adap->dev, "Removing %s at 0x%x\n", client->name,
@@ -974,7 +1062,7 @@ int i2c_del_adapter(struct i2c_adapter *adap)
list_del(&client->detected);
i2c_unregister_device(client);
}
- i2c_unlock_adapter(adap);
+ mutex_unlock(&adap->userspace_clients_lock);
/* Detach any active clients. This can't fail, thus we do not
checking the returned value. */
@@ -1229,12 +1317,12 @@ int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
#endif
if (in_atomic() || irqs_disabled()) {
- ret = rt_mutex_trylock(&adap->bus_lock);
+ ret = i2c_trylock_adapter(adap);
if (!ret)
/* I2C activity is ongoing. */
return -EAGAIN;
} else {
- rt_mutex_lock(&adap->bus_lock);
+ i2c_lock_adapter(adap);
}
/* Retry automatically on arbitration loss */
@@ -1246,7 +1334,7 @@ int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
if (time_after(jiffies, orig_jiffies + adap->timeout))
break;
}
- rt_mutex_unlock(&adap->bus_lock);
+ i2c_unlock_adapter(adap);
return ret;
} else {
@@ -1341,13 +1429,17 @@ static int i2c_default_probe(struct i2c_adapter *adap, unsigned short addr)
I2C_SMBUS_BYTE_DATA, &dummy);
else
#endif
- if ((addr & ~0x07) == 0x30 || (addr & ~0x0f) == 0x50
- || !i2c_check_functionality(adap, I2C_FUNC_SMBUS_QUICK))
- err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0,
- I2C_SMBUS_BYTE, &dummy);
- else
+ if (!((addr & ~0x07) == 0x30 || (addr & ~0x0f) == 0x50)
+ && i2c_check_functionality(adap, I2C_FUNC_SMBUS_QUICK))
err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_WRITE, 0,
I2C_SMBUS_QUICK, NULL);
+ else if (i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE))
+ err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0,
+ I2C_SMBUS_BYTE, &dummy);
+ else {
+ dev_warn(&adap->dev, "No suitable probing method supported\n");
+ err = -EOPNOTSUPP;
+ }
return err >= 0;
}
@@ -1428,16 +1520,6 @@ static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver)
if (!(adapter->class & driver->class))
goto exit_free;
- /* Stop here if the bus doesn't support probing */
- if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_READ_BYTE)) {
- if (address_list[0] == I2C_CLIENT_END)
- goto exit_free;
-
- dev_warn(&adapter->dev, "Probing not supported\n");
- err = -EOPNOTSUPP;
- goto exit_free;
- }
-
for (i = 0; address_list[i] != I2C_CLIENT_END; i += 1) {
dev_dbg(&adapter->dev, "found normal entry for adapter %d, "
"addr 0x%02x\n", adap_id, address_list[i]);
@@ -1452,18 +1534,23 @@ static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver)
return err;
}
+int i2c_probe_func_quick_read(struct i2c_adapter *adap, unsigned short addr)
+{
+ return i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0,
+ I2C_SMBUS_QUICK, NULL) >= 0;
+}
+EXPORT_SYMBOL_GPL(i2c_probe_func_quick_read);
+
struct i2c_client *
i2c_new_probed_device(struct i2c_adapter *adap,
struct i2c_board_info *info,
- unsigned short const *addr_list)
+ unsigned short const *addr_list,
+ int (*probe)(struct i2c_adapter *, unsigned short addr))
{
int i;
- /* Stop here if the bus doesn't support probing */
- if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE)) {
- dev_err(&adap->dev, "Probing not supported\n");
- return NULL;
- }
+ if (!probe)
+ probe = i2c_default_probe;
for (i = 0; addr_list[i] != I2C_CLIENT_END; i++) {
/* Check address validity */
@@ -1481,7 +1568,7 @@ i2c_new_probed_device(struct i2c_adapter *adap,
}
/* Test address responsiveness */
- if (i2c_default_probe(adap, addr_list[i]))
+ if (probe(adap, addr_list[i]))
break;
}
@@ -1993,7 +2080,7 @@ s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, unsigned short flags,
flags &= I2C_M_TEN | I2C_CLIENT_PEC;
if (adapter->algo->smbus_xfer) {
- rt_mutex_lock(&adapter->bus_lock);
+ i2c_lock_adapter(adapter);
/* Retry automatically on arbitration loss */
orig_jiffies = jiffies;
@@ -2007,7 +2094,7 @@ s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, unsigned short flags,
orig_jiffies + adapter->timeout))
break;
}
- rt_mutex_unlock(&adapter->bus_lock);
+ i2c_unlock_adapter(adapter);
} else
res = i2c_smbus_xfer_emulated(adapter, addr, flags, read_write,
command, protocol, data);
diff --git a/drivers/i2c/i2c-dev.c b/drivers/i2c/i2c-dev.c
index e0694e4..5f3a52d 100644
--- a/drivers/i2c/i2c-dev.c
+++ b/drivers/i2c/i2c-dev.c
@@ -167,13 +167,9 @@ static ssize_t i2cdev_write(struct file *file, const char __user *buf,
if (count > 8192)
count = 8192;
- tmp = kmalloc(count, GFP_KERNEL);
- if (tmp == NULL)
- return -ENOMEM;
- if (copy_from_user(tmp, buf, count)) {
- kfree(tmp);
- return -EFAULT;
- }
+ tmp = memdup_user(buf, count);
+ if (IS_ERR(tmp))
+ return PTR_ERR(tmp);
pr_debug("i2c-dev: i2c-%d writing %zu bytes.\n",
iminor(file->f_path.dentry->d_inode), count);
@@ -193,12 +189,50 @@ static int i2cdev_check(struct device *dev, void *addrp)
return dev->driver ? -EBUSY : 0;
}
+/* walk up mux tree */
+static int i2cdev_check_mux_parents(struct i2c_adapter *adapter, int addr)
+{
+ int result;
+
+ result = device_for_each_child(&adapter->dev, &addr, i2cdev_check);
+
+ if (!result && i2c_parent_is_i2c_adapter(adapter))
+ result = i2cdev_check_mux_parents(
+ to_i2c_adapter(adapter->dev.parent), addr);
+
+ return result;
+}
+
+/* recurse down mux tree */
+static int i2cdev_check_mux_children(struct device *dev, void *addrp)
+{
+ int result;
+
+ if (dev->type == &i2c_adapter_type)
+ result = device_for_each_child(dev, addrp,
+ i2cdev_check_mux_children);
+ else
+ result = i2cdev_check(dev, addrp);
+
+ return result;
+}
+
/* This address checking function differs from the one in i2c-core
in that it considers an address with a registered device, but no
driver bound to it, as NOT busy. */
static int i2cdev_check_addr(struct i2c_adapter *adapter, unsigned int addr)
{
- return device_for_each_child(&adapter->dev, &addr, i2cdev_check);
+ int result = 0;
+
+ if (i2c_parent_is_i2c_adapter(adapter))
+ result = i2cdev_check_mux_parents(
+ to_i2c_adapter(adapter->dev.parent), addr);
+
+ if (!result)
+ result = device_for_each_child(&adapter->dev, &addr,
+ i2cdev_check_mux_children);
+
+ return result;
}
static noinline int i2cdev_ioctl_rdrw(struct i2c_client *client,
@@ -219,9 +253,7 @@ static noinline int i2cdev_ioctl_rdrw(struct i2c_client *client,
if (rdwr_arg.nmsgs > I2C_RDRW_IOCTL_MAX_MSGS)
return -EINVAL;
- rdwr_pa = (struct i2c_msg *)
- kmalloc(rdwr_arg.nmsgs * sizeof(struct i2c_msg),
- GFP_KERNEL);
+ rdwr_pa = kmalloc(rdwr_arg.nmsgs * sizeof(struct i2c_msg), GFP_KERNEL);
if (!rdwr_pa)
return -ENOMEM;
@@ -247,15 +279,9 @@ static noinline int i2cdev_ioctl_rdrw(struct i2c_client *client,
break;
}
data_ptrs[i] = (u8 __user *)rdwr_pa[i].buf;
- rdwr_pa[i].buf = kmalloc(rdwr_pa[i].len, GFP_KERNEL);
- if (rdwr_pa[i].buf == NULL) {
- res = -ENOMEM;
- break;
- }
- if (copy_from_user(rdwr_pa[i].buf, data_ptrs[i],
- rdwr_pa[i].len)) {
- ++i; /* Needs to be kfreed too */
- res = -EFAULT;
+ rdwr_pa[i].buf = memdup_user(data_ptrs[i], rdwr_pa[i].len);
+ if (IS_ERR(rdwr_pa[i].buf)) {
+ res = PTR_ERR(rdwr_pa[i].buf);
break;
}
}
diff --git a/drivers/i2c/i2c-mux.c b/drivers/i2c/i2c-mux.c
new file mode 100644
index 0000000..d32a484
--- /dev/null
+++ b/drivers/i2c/i2c-mux.c
@@ -0,0 +1,165 @@
+/*
+ * Multiplexed I2C bus driver.
+ *
+ * Copyright (c) 2008-2009 Rodolfo Giometti <giometti@linux.it>
+ * Copyright (c) 2008-2009 Eurotech S.p.A. <info@eurotech.it>
+ * Copyright (c) 2009-2010 NSN GmbH & Co KG <michael.lawnick.ext@nsn.com>
+ *
+ * Simplifies access to complex multiplexed I2C bus topologies, by presenting
+ * each multiplexed bus segment as an additional I2C adapter.
+ * Supports multi-level mux'ing (mux behind a mux).
+ *
+ * Based on:
+ * i2c-virt.c from Kumar Gala <galak@kernel.crashing.org>
+ * i2c-virtual.c from Ken Harrenstien, Copyright (c) 2004 Google, Inc.
+ * i2c-virtual.c from Brian Kuschak <bkuschak@yahoo.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <linux/i2c-mux.h>
+
+/* multiplexer per channel data */
+struct i2c_mux_priv {
+ struct i2c_adapter adap;
+ struct i2c_algorithm algo;
+
+ struct i2c_adapter *parent;
+ void *mux_dev; /* the mux chip/device */
+ u32 chan_id; /* the channel id */
+
+ int (*select)(struct i2c_adapter *, void *mux_dev, u32 chan_id);
+ int (*deselect)(struct i2c_adapter *, void *mux_dev, u32 chan_id);
+};
+
+static int i2c_mux_master_xfer(struct i2c_adapter *adap,
+ struct i2c_msg msgs[], int num)
+{
+ struct i2c_mux_priv *priv = adap->algo_data;
+ struct i2c_adapter *parent = priv->parent;
+ int ret;
+
+ /* Switch to the right mux port and perform the transfer. */
+
+ ret = priv->select(parent, priv->mux_dev, priv->chan_id);
+ if (ret >= 0)
+ ret = parent->algo->master_xfer(parent, msgs, num);
+ if (priv->deselect)
+ priv->deselect(parent, priv->mux_dev, priv->chan_id);
+
+ return ret;
+}
+
+static int i2c_mux_smbus_xfer(struct i2c_adapter *adap,
+ u16 addr, unsigned short flags,
+ char read_write, u8 command,
+ int size, union i2c_smbus_data *data)
+{
+ struct i2c_mux_priv *priv = adap->algo_data;
+ struct i2c_adapter *parent = priv->parent;
+ int ret;
+
+ /* Select the right mux port and perform the transfer. */
+
+ ret = priv->select(parent, priv->mux_dev, priv->chan_id);
+ if (ret >= 0)
+ ret = parent->algo->smbus_xfer(parent, addr, flags,
+ read_write, command, size, data);
+ if (priv->deselect)
+ priv->deselect(parent, priv->mux_dev, priv->chan_id);
+
+ return ret;
+}
+
+/* Return the parent's functionality */
+static u32 i2c_mux_functionality(struct i2c_adapter *adap)
+{
+ struct i2c_mux_priv *priv = adap->algo_data;
+ struct i2c_adapter *parent = priv->parent;
+
+ return parent->algo->functionality(parent);
+}
+
+struct i2c_adapter *i2c_add_mux_adapter(struct i2c_adapter *parent,
+ void *mux_dev, u32 force_nr, u32 chan_id,
+ int (*select) (struct i2c_adapter *,
+ void *, u32),
+ int (*deselect) (struct i2c_adapter *,
+ void *, u32))
+{
+ struct i2c_mux_priv *priv;
+ int ret;
+
+ priv = kzalloc(sizeof(struct i2c_mux_priv), GFP_KERNEL);
+ if (!priv)
+ return NULL;
+
+ /* Set up private adapter data */
+ priv->parent = parent;
+ priv->mux_dev = mux_dev;
+ priv->chan_id = chan_id;
+ priv->select = select;
+ priv->deselect = deselect;
+
+ /* Need to do algo dynamically because we don't know ahead
+ * of time what sort of physical adapter we'll be dealing with.
+ */
+ if (parent->algo->master_xfer)
+ priv->algo.master_xfer = i2c_mux_master_xfer;
+ if (parent->algo->smbus_xfer)
+ priv->algo.smbus_xfer = i2c_mux_smbus_xfer;
+ priv->algo.functionality = i2c_mux_functionality;
+
+ /* Now fill out new adapter structure */
+ snprintf(priv->adap.name, sizeof(priv->adap.name),
+ "i2c-%d-mux (chan_id %d)", i2c_adapter_id(parent), chan_id);
+ priv->adap.owner = THIS_MODULE;
+ priv->adap.id = parent->id;
+ priv->adap.algo = &priv->algo;
+ priv->adap.algo_data = priv;
+ priv->adap.dev.parent = &parent->dev;
+
+ if (force_nr) {
+ priv->adap.nr = force_nr;
+ ret = i2c_add_numbered_adapter(&priv->adap);
+ } else {
+ ret = i2c_add_adapter(&priv->adap);
+ }
+ if (ret < 0) {
+ dev_err(&parent->dev,
+ "failed to add mux-adapter (error=%d)\n",
+ ret);
+ kfree(priv);
+ return NULL;
+ }
+
+ dev_info(&parent->dev, "Added multiplexed i2c bus %d\n",
+ i2c_adapter_id(&priv->adap));
+
+ return &priv->adap;
+}
+EXPORT_SYMBOL_GPL(i2c_add_mux_adapter);
+
+int i2c_del_mux_adapter(struct i2c_adapter *adap)
+{
+ struct i2c_mux_priv *priv = adap->algo_data;
+ int ret;
+
+ ret = i2c_del_adapter(adap);
+ if (ret < 0)
+ return ret;
+ kfree(priv);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(i2c_del_mux_adapter);
+
+MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");
+MODULE_DESCRIPTION("I2C driver for multiplexed I2C busses");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/i2c/muxes/Kconfig b/drivers/i2c/muxes/Kconfig
new file mode 100644
index 0000000..4c9a99c
--- /dev/null
+++ b/drivers/i2c/muxes/Kconfig
@@ -0,0 +1,18 @@
+#
+# Multiplexer I2C chip drivers configuration
+#
+
+menu "Multiplexer I2C Chip support"
+ depends on I2C_MUX
+
+config I2C_MUX_PCA954x
+ tristate "Philips PCA954x I2C Mux/switches"
+ depends on EXPERIMENTAL
+ help
+ If you say yes here you get support for the Philips PCA954x
+ I2C mux/switch devices.
+
+ This driver can also be built as a module. If so, the module
+ will be called pca954x.
+
+endmenu
diff --git a/drivers/i2c/muxes/Makefile b/drivers/i2c/muxes/Makefile
new file mode 100644
index 0000000..bd83b527
--- /dev/null
+++ b/drivers/i2c/muxes/Makefile
@@ -0,0 +1,8 @@
+#
+# Makefile for multiplexer I2C chip drivers.
+
+obj-$(CONFIG_I2C_MUX_PCA954x) += pca954x.o
+
+ifeq ($(CONFIG_I2C_DEBUG_BUS),y)
+EXTRA_CFLAGS += -DDEBUG
+endif
diff --git a/drivers/i2c/muxes/pca954x.c b/drivers/i2c/muxes/pca954x.c
new file mode 100644
index 0000000..6f9accf
--- /dev/null
+++ b/drivers/i2c/muxes/pca954x.c
@@ -0,0 +1,301 @@
+/*
+ * I2C multiplexer
+ *
+ * Copyright (c) 2008-2009 Rodolfo Giometti <giometti@linux.it>
+ * Copyright (c) 2008-2009 Eurotech S.p.A. <info@eurotech.it>
+ *
+ * This module supports the PCA954x series of I2C multiplexer/switch chips
+ * made by Philips Semiconductors.
+ * This includes the:
+ * PCA9540, PCA9542, PCA9543, PCA9544, PCA9545, PCA9546, PCA9547
+ * and PCA9548.
+ *
+ * These chips are all controlled via the I2C bus itself, and all have a
+ * single 8-bit register. The upstream "parent" bus fans out to two,
+ * four, or eight downstream busses or channels; which of these
+ * are selected is determined by the chip type and register contents. A
+ * mux can select only one sub-bus at a time; a switch can select any
+ * combination simultaneously.
+ *
+ * Based on:
+ * pca954x.c from Kumar Gala <galak@kernel.crashing.org>
+ * Copyright (C) 2006
+ *
+ * Based on:
+ * pca954x.c from Ken Harrenstien
+ * Copyright (C) 2004 Google, Inc. (Ken Harrenstien)
+ *
+ * Based on:
+ * i2c-virtual_cb.c from Brian Kuschak <bkuschak@yahoo.com>
+ * and
+ * pca9540.c from Jean Delvare <khali@linux-fr.org>.
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/device.h>
+#include <linux/i2c.h>
+#include <linux/i2c-mux.h>
+
+#include <linux/i2c/pca954x.h>
+
+#define PCA954X_MAX_NCHANS 8
+
+enum pca_type {
+ pca_9540,
+ pca_9542,
+ pca_9543,
+ pca_9544,
+ pca_9545,
+ pca_9546,
+ pca_9547,
+ pca_9548,
+};
+
+struct pca954x {
+ enum pca_type type;
+ struct i2c_adapter *virt_adaps[PCA954X_MAX_NCHANS];
+
+ u8 last_chan; /* last register value */
+};
+
+struct chip_desc {
+ u8 nchans;
+ u8 enable; /* used for muxes only */
+ enum muxtype {
+ pca954x_ismux = 0,
+ pca954x_isswi
+ } muxtype;
+};
+
+/* Provide specs for the PCA954x types we know about */
+static const struct chip_desc chips[] = {
+ [pca_9540] = {
+ .nchans = 2,
+ .enable = 0x4,
+ .muxtype = pca954x_ismux,
+ },
+ [pca_9543] = {
+ .nchans = 2,
+ .muxtype = pca954x_isswi,
+ },
+ [pca_9544] = {
+ .nchans = 4,
+ .enable = 0x4,
+ .muxtype = pca954x_ismux,
+ },
+ [pca_9545] = {
+ .nchans = 4,
+ .muxtype = pca954x_isswi,
+ },
+ [pca_9547] = {
+ .nchans = 8,
+ .enable = 0x8,
+ .muxtype = pca954x_ismux,
+ },
+ [pca_9548] = {
+ .nchans = 8,
+ .muxtype = pca954x_isswi,
+ },
+};
+
+static const struct i2c_device_id pca954x_id[] = {
+ { "pca9540", pca_9540 },
+ { "pca9542", pca_9540 },
+ { "pca9543", pca_9543 },
+ { "pca9544", pca_9544 },
+ { "pca9545", pca_9545 },
+ { "pca9546", pca_9545 },
+ { "pca9547", pca_9547 },
+ { "pca9548", pca_9548 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, pca954x_id);
+
+/* Write to mux register. Don't use i2c_transfer()/i2c_smbus_xfer()
+ for this as they will try to lock adapter a second time */
+static int pca954x_reg_write(struct i2c_adapter *adap,
+ struct i2c_client *client, u8 val)
+{
+ int ret = -ENODEV;
+
+ if (adap->algo->master_xfer) {
+ struct i2c_msg msg;
+ char buf[1];
+
+ msg.addr = client->addr;
+ msg.flags = 0;
+ msg.len = 1;
+ buf[0] = val;
+ msg.buf = buf;
+ ret = adap->algo->master_xfer(adap, &msg, 1);
+ } else {
+ union i2c_smbus_data data;
+ ret = adap->algo->smbus_xfer(adap, client->addr,
+ client->flags,
+ I2C_SMBUS_WRITE,
+ val, I2C_SMBUS_BYTE, &data);
+ }
+
+ return ret;
+}
+
+static int pca954x_select_chan(struct i2c_adapter *adap,
+ void *client, u32 chan)
+{
+ struct pca954x *data = i2c_get_clientdata(client);
+ const struct chip_desc *chip = &chips[data->type];
+ u8 regval;
+ int ret = 0;
+
+ /* we make switches look like muxes, not sure how to be smarter */
+ if (chip->muxtype == pca954x_ismux)
+ regval = chan | chip->enable;
+ else
+ regval = 1 << chan;
+
+ /* Only select the channel if its different from the last channel */
+ if (data->last_chan != regval) {
+ ret = pca954x_reg_write(adap, client, regval);
+ data->last_chan = regval;
+ }
+
+ return ret;
+}
+
+static int pca954x_deselect_mux(struct i2c_adapter *adap,
+ void *client, u32 chan)
+{
+ struct pca954x *data = i2c_get_clientdata(client);
+
+ /* Deselect active channel */
+ data->last_chan = 0;
+ return pca954x_reg_write(adap, client, data->last_chan);
+}
+
+/*
+ * I2C init/probing/exit functions
+ */
+static int __devinit pca954x_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct i2c_adapter *adap = to_i2c_adapter(client->dev.parent);
+ struct pca954x_platform_data *pdata = client->dev.platform_data;
+ int num, force;
+ struct pca954x *data;
+ int ret = -ENODEV;
+
+ if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_BYTE))
+ goto err;
+
+ data = kzalloc(sizeof(struct pca954x), GFP_KERNEL);
+ if (!data) {
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ i2c_set_clientdata(client, data);
+
+ /* Read the mux register at addr to verify
+ * that the mux is in fact present.
+ */
+ if (i2c_smbus_read_byte(client) < 0) {
+ dev_warn(&client->dev, "probe failed\n");
+ goto exit_free;
+ }
+
+ data->type = id->driver_data;
+ data->last_chan = 0; /* force the first selection */
+
+ /* Now create an adapter for each channel */
+ for (num = 0; num < chips[data->type].nchans; num++) {
+ force = 0; /* dynamic adap number */
+ if (pdata) {
+ if (num < pdata->num_modes)
+ /* force static number */
+ force = pdata->modes[num].adap_id;
+ else
+ /* discard unconfigured channels */
+ break;
+ }
+
+ data->virt_adaps[num] =
+ i2c_add_mux_adapter(adap, client,
+ force, num, pca954x_select_chan,
+ (pdata && pdata->modes[num].deselect_on_exit)
+ ? pca954x_deselect_mux : NULL);
+
+ if (data->virt_adaps[num] == NULL) {
+ ret = -ENODEV;
+ dev_err(&client->dev,
+ "failed to register multiplexed adapter"
+ " %d as bus %d\n", num, force);
+ goto virt_reg_failed;
+ }
+ }
+
+ dev_info(&client->dev,
+ "registered %d multiplexed busses for I2C %s %s\n",
+ num, chips[data->type].muxtype == pca954x_ismux
+ ? "mux" : "switch", client->name);
+
+ return 0;
+
+virt_reg_failed:
+ for (num--; num >= 0; num--)
+ i2c_del_mux_adapter(data->virt_adaps[num]);
+exit_free:
+ kfree(data);
+err:
+ return ret;
+}
+
+static int __devexit pca954x_remove(struct i2c_client *client)
+{
+ struct pca954x *data = i2c_get_clientdata(client);
+ const struct chip_desc *chip = &chips[data->type];
+ int i, err;
+
+ for (i = 0; i < chip->nchans; ++i)
+ if (data->virt_adaps[i]) {
+ err = i2c_del_mux_adapter(data->virt_adaps[i]);
+ if (err)
+ return err;
+ data->virt_adaps[i] = NULL;
+ }
+
+ kfree(data);
+ return 0;
+}
+
+static struct i2c_driver pca954x_driver = {
+ .driver = {
+ .name = "pca954x",
+ .owner = THIS_MODULE,
+ },
+ .probe = pca954x_probe,
+ .remove = __devexit_p(pca954x_remove),
+ .id_table = pca954x_id,
+};
+
+static int __init pca954x_init(void)
+{
+ return i2c_add_driver(&pca954x_driver);
+}
+
+static void __exit pca954x_exit(void)
+{
+ i2c_del_driver(&pca954x_driver);
+}
+
+module_init(pca954x_init);
+module_exit(pca954x_exit);
+
+MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");
+MODULE_DESCRIPTION("PCA954x I2C mux/switch driver");
+MODULE_LICENSE("GPL v2");
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