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path: root/drivers/spi/spi-pxa2xx.c
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Diffstat (limited to 'drivers/spi/spi-pxa2xx.c')
-rw-r--r--drivers/spi/spi-pxa2xx.c257
1 files changed, 158 insertions, 99 deletions
diff --git a/drivers/spi/spi-pxa2xx.c b/drivers/spi/spi-pxa2xx.c
index a8ef38e..b25dc71 100644
--- a/drivers/spi/spi-pxa2xx.c
+++ b/drivers/spi/spi-pxa2xx.c
@@ -13,6 +13,7 @@
* GNU General Public License for more details.
*/
+#include <linux/bitops.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/device.h>
@@ -61,9 +62,13 @@ MODULE_ALIAS("platform:pxa2xx-spi");
| QUARK_X1000_SSCR1_TFT \
| SSCR1_SPH | SSCR1_SPO | SSCR1_LBM)
-#define GENERAL_REG_RXTO_HOLDOFF_DISABLE BIT(24)
-#define SPI_CS_CONTROL_SW_MODE BIT(0)
-#define SPI_CS_CONTROL_CS_HIGH BIT(1)
+#define LPSS_GENERAL_REG_RXTO_HOLDOFF_DISABLE BIT(24)
+#define LPSS_CS_CONTROL_SW_MODE BIT(0)
+#define LPSS_CS_CONTROL_CS_HIGH BIT(1)
+#define LPSS_CS_CONTROL_CS_SEL_SHIFT 8
+#define LPSS_CS_CONTROL_CS_SEL_MASK (3 << LPSS_CS_CONTROL_CS_SEL_SHIFT)
+#define LPSS_CAPS_CS_EN_SHIFT 9
+#define LPSS_CAPS_CS_EN_MASK (0xf << LPSS_CAPS_CS_EN_SHIFT)
struct lpss_config {
/* LPSS offset from drv_data->ioaddr */
@@ -72,6 +77,7 @@ struct lpss_config {
int reg_general;
int reg_ssp;
int reg_cs_ctrl;
+ int reg_capabilities;
/* FIFO thresholds */
u32 rx_threshold;
u32 tx_threshold_lo;
@@ -85,6 +91,7 @@ static const struct lpss_config lpss_platforms[] = {
.reg_general = 0x08,
.reg_ssp = 0x0c,
.reg_cs_ctrl = 0x18,
+ .reg_capabilities = -1,
.rx_threshold = 64,
.tx_threshold_lo = 160,
.tx_threshold_hi = 224,
@@ -94,6 +101,7 @@ static const struct lpss_config lpss_platforms[] = {
.reg_general = 0x08,
.reg_ssp = 0x0c,
.reg_cs_ctrl = 0x18,
+ .reg_capabilities = -1,
.rx_threshold = 64,
.tx_threshold_lo = 160,
.tx_threshold_hi = 224,
@@ -103,10 +111,21 @@ static const struct lpss_config lpss_platforms[] = {
.reg_general = -1,
.reg_ssp = 0x20,
.reg_cs_ctrl = 0x24,
+ .reg_capabilities = 0xfc,
.rx_threshold = 1,
.tx_threshold_lo = 32,
.tx_threshold_hi = 56,
},
+ { /* LPSS_BXT_SSP */
+ .offset = 0x200,
+ .reg_general = -1,
+ .reg_ssp = 0x20,
+ .reg_cs_ctrl = 0x24,
+ .reg_capabilities = 0xfc,
+ .rx_threshold = 1,
+ .tx_threshold_lo = 16,
+ .tx_threshold_hi = 48,
+ },
};
static inline const struct lpss_config
@@ -121,6 +140,7 @@ static bool is_lpss_ssp(const struct driver_data *drv_data)
case LPSS_LPT_SSP:
case LPSS_BYT_SSP:
case LPSS_SPT_SSP:
+ case LPSS_BXT_SSP:
return true;
default:
return false;
@@ -249,7 +269,9 @@ static void lpss_ssp_setup(struct driver_data *drv_data)
drv_data->lpss_base = drv_data->ioaddr + config->offset;
/* Enable software chip select control */
- value = SPI_CS_CONTROL_SW_MODE | SPI_CS_CONTROL_CS_HIGH;
+ value = __lpss_ssp_read_priv(drv_data, config->reg_cs_ctrl);
+ value &= ~(LPSS_CS_CONTROL_SW_MODE | LPSS_CS_CONTROL_CS_HIGH);
+ value |= LPSS_CS_CONTROL_SW_MODE | LPSS_CS_CONTROL_CS_HIGH;
__lpss_ssp_write_priv(drv_data, config->reg_cs_ctrl, value);
/* Enable multiblock DMA transfers */
@@ -259,7 +281,7 @@ static void lpss_ssp_setup(struct driver_data *drv_data)
if (config->reg_general >= 0) {
value = __lpss_ssp_read_priv(drv_data,
config->reg_general);
- value |= GENERAL_REG_RXTO_HOLDOFF_DISABLE;
+ value |= LPSS_GENERAL_REG_RXTO_HOLDOFF_DISABLE;
__lpss_ssp_write_priv(drv_data,
config->reg_general, value);
}
@@ -269,15 +291,34 @@ static void lpss_ssp_setup(struct driver_data *drv_data)
static void lpss_ssp_cs_control(struct driver_data *drv_data, bool enable)
{
const struct lpss_config *config;
- u32 value;
+ u32 value, cs;
config = lpss_get_config(drv_data);
value = __lpss_ssp_read_priv(drv_data, config->reg_cs_ctrl);
- if (enable)
- value &= ~SPI_CS_CONTROL_CS_HIGH;
- else
- value |= SPI_CS_CONTROL_CS_HIGH;
+ if (enable) {
+ cs = drv_data->cur_msg->spi->chip_select;
+ cs <<= LPSS_CS_CONTROL_CS_SEL_SHIFT;
+ if (cs != (value & LPSS_CS_CONTROL_CS_SEL_MASK)) {
+ /*
+ * When switching another chip select output active
+ * the output must be selected first and wait 2 ssp_clk
+ * cycles before changing state to active. Otherwise
+ * a short glitch will occur on the previous chip
+ * select since output select is latched but state
+ * control is not.
+ */
+ value &= ~LPSS_CS_CONTROL_CS_SEL_MASK;
+ value |= cs;
+ __lpss_ssp_write_priv(drv_data,
+ config->reg_cs_ctrl, value);
+ ndelay(1000000000 /
+ (drv_data->master->max_speed_hz / 2));
+ }
+ value &= ~LPSS_CS_CONTROL_CS_HIGH;
+ } else {
+ value |= LPSS_CS_CONTROL_CS_HIGH;
+ }
__lpss_ssp_write_priv(drv_data, config->reg_cs_ctrl, value);
}
@@ -734,7 +775,7 @@ static unsigned int quark_x1000_get_clk_div(int rate, u32 *dds)
mul = (1 << 24) >> 1;
/* Calculate initial quot */
- q1 = DIV_ROUND_CLOSEST(fref1, rate);
+ q1 = DIV_ROUND_UP(fref1, rate);
/* Scale q1 if it's too big */
if (q1 > 256) {
@@ -759,7 +800,7 @@ static unsigned int quark_x1000_get_clk_div(int rate, u32 *dds)
/* Case 2 */
- q2 = DIV_ROUND_CLOSEST(fref2, rate);
+ q2 = DIV_ROUND_UP(fref2, rate);
r2 = abs(fref2 / q2 - rate);
/*
@@ -778,13 +819,13 @@ static unsigned int quark_x1000_get_clk_div(int rate, u32 *dds)
mul = (1 << 24) * 2 / 5;
}
- /* Check case 3 only If the divisor is big enough */
+ /* Check case 3 only if the divisor is big enough */
if (fref / rate >= 80) {
u64 fssp;
u32 m;
/* Calculate initial quot */
- q1 = DIV_ROUND_CLOSEST(fref, rate);
+ q1 = DIV_ROUND_UP(fref, rate);
m = (1 << 24) / q1;
/* Get the remainder */
@@ -806,7 +847,7 @@ static unsigned int quark_x1000_get_clk_div(int rate, u32 *dds)
static unsigned int ssp_get_clk_div(struct driver_data *drv_data, int rate)
{
- unsigned long ssp_clk = drv_data->max_clk_rate;
+ unsigned long ssp_clk = drv_data->master->max_speed_hz;
const struct ssp_device *ssp = drv_data->ssp;
rate = min_t(int, ssp_clk, rate);
@@ -818,8 +859,9 @@ static unsigned int ssp_get_clk_div(struct driver_data *drv_data, int rate)
}
static unsigned int pxa2xx_ssp_get_clk_div(struct driver_data *drv_data,
- struct chip_data *chip, int rate)
+ int rate)
{
+ struct chip_data *chip = drv_data->cur_chip;
unsigned int clk_div;
switch (drv_data->ssp_type) {
@@ -922,52 +964,55 @@ static void pump_transfers(unsigned long data)
drv_data->read = drv_data->rx ? chip->read : null_reader;
/* Change speed and bit per word on a per transfer */
- cr0 = chip->cr0;
- if (transfer->speed_hz || transfer->bits_per_word) {
-
- bits = chip->bits_per_word;
- speed = chip->speed_hz;
-
- if (transfer->speed_hz)
- speed = transfer->speed_hz;
-
- if (transfer->bits_per_word)
- bits = transfer->bits_per_word;
-
- clk_div = pxa2xx_ssp_get_clk_div(drv_data, chip, speed);
-
- if (bits <= 8) {
- drv_data->n_bytes = 1;
- drv_data->read = drv_data->read != null_reader ?
- u8_reader : null_reader;
- drv_data->write = drv_data->write != null_writer ?
- u8_writer : null_writer;
- } else if (bits <= 16) {
- drv_data->n_bytes = 2;
- drv_data->read = drv_data->read != null_reader ?
- u16_reader : null_reader;
- drv_data->write = drv_data->write != null_writer ?
- u16_writer : null_writer;
- } else if (bits <= 32) {
- drv_data->n_bytes = 4;
- drv_data->read = drv_data->read != null_reader ?
- u32_reader : null_reader;
- drv_data->write = drv_data->write != null_writer ?
- u32_writer : null_writer;
- }
- /* if bits/word is changed in dma mode, then must check the
- * thresholds and burst also */
- if (chip->enable_dma) {
- if (pxa2xx_spi_set_dma_burst_and_threshold(chip,
- message->spi,
- bits, &dma_burst,
- &dma_thresh))
- dev_warn_ratelimited(&message->spi->dev,
- "pump_transfers: DMA burst size reduced to match bits_per_word\n");
- }
-
- cr0 = pxa2xx_configure_sscr0(drv_data, clk_div, bits);
+ bits = transfer->bits_per_word;
+ speed = transfer->speed_hz;
+
+ clk_div = pxa2xx_ssp_get_clk_div(drv_data, speed);
+
+ if (bits <= 8) {
+ drv_data->n_bytes = 1;
+ drv_data->read = drv_data->read != null_reader ?
+ u8_reader : null_reader;
+ drv_data->write = drv_data->write != null_writer ?
+ u8_writer : null_writer;
+ } else if (bits <= 16) {
+ drv_data->n_bytes = 2;
+ drv_data->read = drv_data->read != null_reader ?
+ u16_reader : null_reader;
+ drv_data->write = drv_data->write != null_writer ?
+ u16_writer : null_writer;
+ } else if (bits <= 32) {
+ drv_data->n_bytes = 4;
+ drv_data->read = drv_data->read != null_reader ?
+ u32_reader : null_reader;
+ drv_data->write = drv_data->write != null_writer ?
+ u32_writer : null_writer;
}
+ /*
+ * if bits/word is changed in dma mode, then must check the
+ * thresholds and burst also
+ */
+ if (chip->enable_dma) {
+ if (pxa2xx_spi_set_dma_burst_and_threshold(chip,
+ message->spi,
+ bits, &dma_burst,
+ &dma_thresh))
+ dev_warn_ratelimited(&message->spi->dev,
+ "pump_transfers: DMA burst size reduced to match bits_per_word\n");
+ }
+
+ /* NOTE: PXA25x_SSP _could_ use external clocking ... */
+ cr0 = pxa2xx_configure_sscr0(drv_data, clk_div, bits);
+ if (!pxa25x_ssp_comp(drv_data))
+ dev_dbg(&message->spi->dev, "%u Hz actual, %s\n",
+ drv_data->master->max_speed_hz
+ / (1 + ((cr0 & SSCR0_SCR(0xfff)) >> 8)),
+ chip->enable_dma ? "DMA" : "PIO");
+ else
+ dev_dbg(&message->spi->dev, "%u Hz actual, %s\n",
+ drv_data->master->max_speed_hz / 2
+ / (1 + ((cr0 & SSCR0_SCR(0x0ff)) >> 8)),
+ chip->enable_dma ? "DMA" : "PIO");
message->state = RUNNING_STATE;
@@ -1111,7 +1156,6 @@ static int setup(struct spi_device *spi)
struct chip_data *chip;
const struct lpss_config *config;
struct driver_data *drv_data = spi_master_get_devdata(spi->master);
- unsigned int clk_div;
uint tx_thres, tx_hi_thres, rx_thres;
switch (drv_data->ssp_type) {
@@ -1123,6 +1167,7 @@ static int setup(struct spi_device *spi)
case LPSS_LPT_SSP:
case LPSS_BYT_SSP:
case LPSS_SPT_SSP:
+ case LPSS_BXT_SSP:
config = lpss_get_config(drv_data);
tx_thres = config->tx_threshold_lo;
tx_hi_thres = config->tx_threshold_hi;
@@ -1203,11 +1248,6 @@ static int setup(struct spi_device *spi)
}
}
- clk_div = pxa2xx_ssp_get_clk_div(drv_data, chip, spi->max_speed_hz);
- chip->speed_hz = spi->max_speed_hz;
-
- chip->cr0 = pxa2xx_configure_sscr0(drv_data, clk_div,
- spi->bits_per_word);
switch (drv_data->ssp_type) {
case QUARK_X1000_SSP:
chip->threshold = (QUARK_X1000_SSCR1_RxTresh(rx_thres)
@@ -1228,18 +1268,6 @@ static int setup(struct spi_device *spi)
if (spi->mode & SPI_LOOP)
chip->cr1 |= SSCR1_LBM;
- /* NOTE: PXA25x_SSP _could_ use external clocking ... */
- if (!pxa25x_ssp_comp(drv_data))
- dev_dbg(&spi->dev, "%ld Hz actual, %s\n",
- drv_data->max_clk_rate
- / (1 + ((chip->cr0 & SSCR0_SCR(0xfff)) >> 8)),
- chip->enable_dma ? "DMA" : "PIO");
- else
- dev_dbg(&spi->dev, "%ld Hz actual, %s\n",
- drv_data->max_clk_rate / 2
- / (1 + ((chip->cr0 & SSCR0_SCR(0x0ff)) >> 8)),
- chip->enable_dma ? "DMA" : "PIO");
-
if (spi->bits_per_word <= 8) {
chip->n_bytes = 1;
chip->read = u8_reader;
@@ -1249,13 +1277,10 @@ static int setup(struct spi_device *spi)
chip->read = u16_reader;
chip->write = u16_writer;
} else if (spi->bits_per_word <= 32) {
- if (!is_quark_x1000_ssp(drv_data))
- chip->cr0 |= SSCR0_EDSS;
chip->n_bytes = 4;
chip->read = u32_reader;
chip->write = u32_writer;
}
- chip->bits_per_word = spi->bits_per_word;
spi_set_ctldata(spi, chip);
@@ -1279,6 +1304,7 @@ static void cleanup(struct spi_device *spi)
kfree(chip);
}
+#ifdef CONFIG_PCI
#ifdef CONFIG_ACPI
static const struct acpi_device_id pxa2xx_spi_acpi_match[] = {
@@ -1292,6 +1318,23 @@ static const struct acpi_device_id pxa2xx_spi_acpi_match[] = {
};
MODULE_DEVICE_TABLE(acpi, pxa2xx_spi_acpi_match);
+static int pxa2xx_spi_get_port_id(struct acpi_device *adev)
+{
+ unsigned int devid;
+ int port_id = -1;
+
+ if (adev && adev->pnp.unique_id &&
+ !kstrtouint(adev->pnp.unique_id, 0, &devid))
+ port_id = devid;
+ return port_id;
+}
+#else /* !CONFIG_ACPI */
+static int pxa2xx_spi_get_port_id(struct acpi_device *adev)
+{
+ return -1;
+}
+#endif
+
/*
* PCI IDs of compound devices that integrate both host controller and private
* integrated DMA engine. Please note these are not used in module
@@ -1304,6 +1347,14 @@ static const struct pci_device_id pxa2xx_spi_pci_compound_match[] = {
/* SPT-H */
{ PCI_VDEVICE(INTEL, 0xa129), LPSS_SPT_SSP },
{ PCI_VDEVICE(INTEL, 0xa12a), LPSS_SPT_SSP },
+ /* BXT */
+ { PCI_VDEVICE(INTEL, 0x0ac2), LPSS_BXT_SSP },
+ { PCI_VDEVICE(INTEL, 0x0ac4), LPSS_BXT_SSP },
+ { PCI_VDEVICE(INTEL, 0x0ac6), LPSS_BXT_SSP },
+ /* APL */
+ { PCI_VDEVICE(INTEL, 0x5ac2), LPSS_BXT_SSP },
+ { PCI_VDEVICE(INTEL, 0x5ac4), LPSS_BXT_SSP },
+ { PCI_VDEVICE(INTEL, 0x5ac6), LPSS_BXT_SSP },
{ },
};
@@ -1318,7 +1369,7 @@ static bool pxa2xx_spi_idma_filter(struct dma_chan *chan, void *param)
}
static struct pxa2xx_spi_master *
-pxa2xx_spi_acpi_get_pdata(struct platform_device *pdev)
+pxa2xx_spi_init_pdata(struct platform_device *pdev)
{
struct pxa2xx_spi_master *pdata;
struct acpi_device *adev;
@@ -1326,18 +1377,18 @@ pxa2xx_spi_acpi_get_pdata(struct platform_device *pdev)
struct resource *res;
const struct acpi_device_id *adev_id = NULL;
const struct pci_device_id *pcidev_id = NULL;
- int devid, type;
+ int type;
- if (!ACPI_HANDLE(&pdev->dev) ||
- acpi_bus_get_device(ACPI_HANDLE(&pdev->dev), &adev))
- return NULL;
+ adev = ACPI_COMPANION(&pdev->dev);
if (dev_is_pci(pdev->dev.parent))
pcidev_id = pci_match_id(pxa2xx_spi_pci_compound_match,
to_pci_dev(pdev->dev.parent));
- else
+ else if (adev)
adev_id = acpi_match_device(pdev->dev.driver->acpi_match_table,
&pdev->dev);
+ else
+ return NULL;
if (adev_id)
type = (int)adev_id->driver_data;
@@ -1371,10 +1422,7 @@ pxa2xx_spi_acpi_get_pdata(struct platform_device *pdev)
ssp->irq = platform_get_irq(pdev, 0);
ssp->type = type;
ssp->pdev = pdev;
-
- ssp->port_id = -1;
- if (adev->pnp.unique_id && !kstrtoint(adev->pnp.unique_id, 0, &devid))
- ssp->port_id = devid;
+ ssp->port_id = pxa2xx_spi_get_port_id(adev);
pdata->num_chipselect = 1;
pdata->enable_dma = true;
@@ -1382,9 +1430,9 @@ pxa2xx_spi_acpi_get_pdata(struct platform_device *pdev)
return pdata;
}
-#else
+#else /* !CONFIG_PCI */
static inline struct pxa2xx_spi_master *
-pxa2xx_spi_acpi_get_pdata(struct platform_device *pdev)
+pxa2xx_spi_init_pdata(struct platform_device *pdev)
{
return NULL;
}
@@ -1397,12 +1445,13 @@ static int pxa2xx_spi_probe(struct platform_device *pdev)
struct spi_master *master;
struct driver_data *drv_data;
struct ssp_device *ssp;
+ const struct lpss_config *config;
int status;
u32 tmp;
platform_info = dev_get_platdata(dev);
if (!platform_info) {
- platform_info = pxa2xx_spi_acpi_get_pdata(pdev);
+ platform_info = pxa2xx_spi_init_pdata(pdev);
if (!platform_info) {
dev_err(&pdev->dev, "missing platform data\n");
return -ENODEV;
@@ -1436,7 +1485,6 @@ static int pxa2xx_spi_probe(struct platform_device *pdev)
master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP;
master->bus_num = ssp->port_id;
- master->num_chipselect = platform_info->num_chipselect;
master->dma_alignment = DMA_ALIGNMENT;
master->cleanup = cleanup;
master->setup = setup;
@@ -1489,7 +1537,7 @@ static int pxa2xx_spi_probe(struct platform_device *pdev)
/* Enable SOC clock */
clk_prepare_enable(ssp->clk);
- drv_data->max_clk_rate = clk_get_rate(ssp->clk);
+ master->max_speed_hz = clk_get_rate(ssp->clk);
/* Load default SSP configuration */
pxa2xx_spi_write(drv_data, SSCR0, 0);
@@ -1522,6 +1570,19 @@ static int pxa2xx_spi_probe(struct platform_device *pdev)
if (is_lpss_ssp(drv_data))
lpss_ssp_setup(drv_data);
+ if (is_lpss_ssp(drv_data)) {
+ lpss_ssp_setup(drv_data);
+ config = lpss_get_config(drv_data);
+ if (config->reg_capabilities >= 0) {
+ tmp = __lpss_ssp_read_priv(drv_data,
+ config->reg_capabilities);
+ tmp &= LPSS_CAPS_CS_EN_MASK;
+ tmp >>= LPSS_CAPS_CS_EN_SHIFT;
+ platform_info->num_chipselect = ffz(tmp);
+ }
+ }
+ master->num_chipselect = platform_info->num_chipselect;
+
tasklet_init(&drv_data->pump_transfers, pump_transfers,
(unsigned long)drv_data);
@@ -1614,8 +1675,6 @@ static int pxa2xx_spi_resume(struct device *dev)
struct ssp_device *ssp = drv_data->ssp;
int status = 0;
- pxa2xx_spi_dma_resume(drv_data);
-
/* Enable the SSP clock */
if (!pm_runtime_suspended(dev))
clk_prepare_enable(ssp->clk);
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