summaryrefslogtreecommitdiffstats
path: root/drivers/gpio/gpio-nomadik.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/gpio/gpio-nomadik.c')
-rw-r--r--drivers/gpio/gpio-nomadik.c1069
1 files changed, 1069 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-nomadik.c b/drivers/gpio/gpio-nomadik.c
new file mode 100644
index 0000000..4961ef9
--- /dev/null
+++ b/drivers/gpio/gpio-nomadik.c
@@ -0,0 +1,1069 @@
+/*
+ * Generic GPIO driver for logic cells found in the Nomadik SoC
+ *
+ * Copyright (C) 2008,2009 STMicroelectronics
+ * Copyright (C) 2009 Alessandro Rubini <rubini@unipv.it>
+ * Rewritten based on work by Prafulla WADASKAR <prafulla.wadaskar@st.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/gpio.h>
+#include <linux/spinlock.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/slab.h>
+
+#include <asm/mach/irq.h>
+
+#include <plat/pincfg.h>
+#include <mach/hardware.h>
+#include <mach/gpio.h>
+
+/*
+ * The GPIO module in the Nomadik family of Systems-on-Chip is an
+ * AMBA device, managing 32 pins and alternate functions. The logic block
+ * is currently used in the Nomadik and ux500.
+ *
+ * Symbols in this file are called "nmk_gpio" for "nomadik gpio"
+ */
+
+#define NMK_GPIO_PER_CHIP 32
+
+struct nmk_gpio_chip {
+ struct gpio_chip chip;
+ void __iomem *addr;
+ struct clk *clk;
+ unsigned int bank;
+ unsigned int parent_irq;
+ int secondary_parent_irq;
+ u32 (*get_secondary_status)(unsigned int bank);
+ void (*set_ioforce)(bool enable);
+ spinlock_t lock;
+ /* Keep track of configured edges */
+ u32 edge_rising;
+ u32 edge_falling;
+ u32 real_wake;
+ u32 rwimsc;
+ u32 fwimsc;
+ u32 slpm;
+ u32 enabled;
+ u32 pull_up;
+};
+
+static struct nmk_gpio_chip *
+nmk_gpio_chips[DIV_ROUND_UP(ARCH_NR_GPIOS, NMK_GPIO_PER_CHIP)];
+
+static DEFINE_SPINLOCK(nmk_gpio_slpm_lock);
+
+#define NUM_BANKS ARRAY_SIZE(nmk_gpio_chips)
+
+static void __nmk_gpio_set_mode(struct nmk_gpio_chip *nmk_chip,
+ unsigned offset, int gpio_mode)
+{
+ u32 bit = 1 << offset;
+ u32 afunc, bfunc;
+
+ afunc = readl(nmk_chip->addr + NMK_GPIO_AFSLA) & ~bit;
+ bfunc = readl(nmk_chip->addr + NMK_GPIO_AFSLB) & ~bit;
+ if (gpio_mode & NMK_GPIO_ALT_A)
+ afunc |= bit;
+ if (gpio_mode & NMK_GPIO_ALT_B)
+ bfunc |= bit;
+ writel(afunc, nmk_chip->addr + NMK_GPIO_AFSLA);
+ writel(bfunc, nmk_chip->addr + NMK_GPIO_AFSLB);
+}
+
+static void __nmk_gpio_set_slpm(struct nmk_gpio_chip *nmk_chip,
+ unsigned offset, enum nmk_gpio_slpm mode)
+{
+ u32 bit = 1 << offset;
+ u32 slpm;
+
+ slpm = readl(nmk_chip->addr + NMK_GPIO_SLPC);
+ if (mode == NMK_GPIO_SLPM_NOCHANGE)
+ slpm |= bit;
+ else
+ slpm &= ~bit;
+ writel(slpm, nmk_chip->addr + NMK_GPIO_SLPC);
+}
+
+static void __nmk_gpio_set_pull(struct nmk_gpio_chip *nmk_chip,
+ unsigned offset, enum nmk_gpio_pull pull)
+{
+ u32 bit = 1 << offset;
+ u32 pdis;
+
+ pdis = readl(nmk_chip->addr + NMK_GPIO_PDIS);
+ if (pull == NMK_GPIO_PULL_NONE) {
+ pdis |= bit;
+ nmk_chip->pull_up &= ~bit;
+ } else {
+ pdis &= ~bit;
+ }
+
+ writel(pdis, nmk_chip->addr + NMK_GPIO_PDIS);
+
+ if (pull == NMK_GPIO_PULL_UP) {
+ nmk_chip->pull_up |= bit;
+ writel(bit, nmk_chip->addr + NMK_GPIO_DATS);
+ } else if (pull == NMK_GPIO_PULL_DOWN) {
+ nmk_chip->pull_up &= ~bit;
+ writel(bit, nmk_chip->addr + NMK_GPIO_DATC);
+ }
+}
+
+static void __nmk_gpio_make_input(struct nmk_gpio_chip *nmk_chip,
+ unsigned offset)
+{
+ writel(1 << offset, nmk_chip->addr + NMK_GPIO_DIRC);
+}
+
+static void __nmk_gpio_set_output(struct nmk_gpio_chip *nmk_chip,
+ unsigned offset, int val)
+{
+ if (val)
+ writel(1 << offset, nmk_chip->addr + NMK_GPIO_DATS);
+ else
+ writel(1 << offset, nmk_chip->addr + NMK_GPIO_DATC);
+}
+
+static void __nmk_gpio_make_output(struct nmk_gpio_chip *nmk_chip,
+ unsigned offset, int val)
+{
+ writel(1 << offset, nmk_chip->addr + NMK_GPIO_DIRS);
+ __nmk_gpio_set_output(nmk_chip, offset, val);
+}
+
+static void __nmk_gpio_set_mode_safe(struct nmk_gpio_chip *nmk_chip,
+ unsigned offset, int gpio_mode,
+ bool glitch)
+{
+ u32 rwimsc = readl(nmk_chip->addr + NMK_GPIO_RWIMSC);
+ u32 fwimsc = readl(nmk_chip->addr + NMK_GPIO_FWIMSC);
+
+ if (glitch && nmk_chip->set_ioforce) {
+ u32 bit = BIT(offset);
+
+ /* Prevent spurious wakeups */
+ writel(rwimsc & ~bit, nmk_chip->addr + NMK_GPIO_RWIMSC);
+ writel(fwimsc & ~bit, nmk_chip->addr + NMK_GPIO_FWIMSC);
+
+ nmk_chip->set_ioforce(true);
+ }
+
+ __nmk_gpio_set_mode(nmk_chip, offset, gpio_mode);
+
+ if (glitch && nmk_chip->set_ioforce) {
+ nmk_chip->set_ioforce(false);
+
+ writel(rwimsc, nmk_chip->addr + NMK_GPIO_RWIMSC);
+ writel(fwimsc, nmk_chip->addr + NMK_GPIO_FWIMSC);
+ }
+}
+
+static void __nmk_config_pin(struct nmk_gpio_chip *nmk_chip, unsigned offset,
+ pin_cfg_t cfg, bool sleep, unsigned int *slpmregs)
+{
+ static const char *afnames[] = {
+ [NMK_GPIO_ALT_GPIO] = "GPIO",
+ [NMK_GPIO_ALT_A] = "A",
+ [NMK_GPIO_ALT_B] = "B",
+ [NMK_GPIO_ALT_C] = "C"
+ };
+ static const char *pullnames[] = {
+ [NMK_GPIO_PULL_NONE] = "none",
+ [NMK_GPIO_PULL_UP] = "up",
+ [NMK_GPIO_PULL_DOWN] = "down",
+ [3] /* illegal */ = "??"
+ };
+ static const char *slpmnames[] = {
+ [NMK_GPIO_SLPM_INPUT] = "input/wakeup",
+ [NMK_GPIO_SLPM_NOCHANGE] = "no-change/no-wakeup",
+ };
+
+ int pin = PIN_NUM(cfg);
+ int pull = PIN_PULL(cfg);
+ int af = PIN_ALT(cfg);
+ int slpm = PIN_SLPM(cfg);
+ int output = PIN_DIR(cfg);
+ int val = PIN_VAL(cfg);
+ bool glitch = af == NMK_GPIO_ALT_C;
+
+ dev_dbg(nmk_chip->chip.dev, "pin %d [%#lx]: af %s, pull %s, slpm %s (%s%s)\n",
+ pin, cfg, afnames[af], pullnames[pull], slpmnames[slpm],
+ output ? "output " : "input",
+ output ? (val ? "high" : "low") : "");
+
+ if (sleep) {
+ int slpm_pull = PIN_SLPM_PULL(cfg);
+ int slpm_output = PIN_SLPM_DIR(cfg);
+ int slpm_val = PIN_SLPM_VAL(cfg);
+
+ af = NMK_GPIO_ALT_GPIO;
+
+ /*
+ * The SLPM_* values are normal values + 1 to allow zero to
+ * mean "same as normal".
+ */
+ if (slpm_pull)
+ pull = slpm_pull - 1;
+ if (slpm_output)
+ output = slpm_output - 1;
+ if (slpm_val)
+ val = slpm_val - 1;
+
+ dev_dbg(nmk_chip->chip.dev, "pin %d: sleep pull %s, dir %s, val %s\n",
+ pin,
+ slpm_pull ? pullnames[pull] : "same",
+ slpm_output ? (output ? "output" : "input") : "same",
+ slpm_val ? (val ? "high" : "low") : "same");
+ }
+
+ if (output)
+ __nmk_gpio_make_output(nmk_chip, offset, val);
+ else {
+ __nmk_gpio_make_input(nmk_chip, offset);
+ __nmk_gpio_set_pull(nmk_chip, offset, pull);
+ }
+
+ /*
+ * If we've backed up the SLPM registers (glitch workaround), modify
+ * the backups since they will be restored.
+ */
+ if (slpmregs) {
+ if (slpm == NMK_GPIO_SLPM_NOCHANGE)
+ slpmregs[nmk_chip->bank] |= BIT(offset);
+ else
+ slpmregs[nmk_chip->bank] &= ~BIT(offset);
+ } else
+ __nmk_gpio_set_slpm(nmk_chip, offset, slpm);
+
+ __nmk_gpio_set_mode_safe(nmk_chip, offset, af, glitch);
+}
+
+/*
+ * Safe sequence used to switch IOs between GPIO and Alternate-C mode:
+ * - Save SLPM registers
+ * - Set SLPM=0 for the IOs you want to switch and others to 1
+ * - Configure the GPIO registers for the IOs that are being switched
+ * - Set IOFORCE=1
+ * - Modify the AFLSA/B registers for the IOs that are being switched
+ * - Set IOFORCE=0
+ * - Restore SLPM registers
+ * - Any spurious wake up event during switch sequence to be ignored and
+ * cleared
+ */
+static void nmk_gpio_glitch_slpm_init(unsigned int *slpm)
+{
+ int i;
+
+ for (i = 0; i < NUM_BANKS; i++) {
+ struct nmk_gpio_chip *chip = nmk_gpio_chips[i];
+ unsigned int temp = slpm[i];
+
+ if (!chip)
+ break;
+
+ slpm[i] = readl(chip->addr + NMK_GPIO_SLPC);
+ writel(temp, chip->addr + NMK_GPIO_SLPC);
+ }
+}
+
+static void nmk_gpio_glitch_slpm_restore(unsigned int *slpm)
+{
+ int i;
+
+ for (i = 0; i < NUM_BANKS; i++) {
+ struct nmk_gpio_chip *chip = nmk_gpio_chips[i];
+
+ if (!chip)
+ break;
+
+ writel(slpm[i], chip->addr + NMK_GPIO_SLPC);
+ }
+}
+
+static int __nmk_config_pins(pin_cfg_t *cfgs, int num, bool sleep)
+{
+ static unsigned int slpm[NUM_BANKS];
+ unsigned long flags;
+ bool glitch = false;
+ int ret = 0;
+ int i;
+
+ for (i = 0; i < num; i++) {
+ if (PIN_ALT(cfgs[i]) == NMK_GPIO_ALT_C) {
+ glitch = true;
+ break;
+ }
+ }
+
+ spin_lock_irqsave(&nmk_gpio_slpm_lock, flags);
+
+ if (glitch) {
+ memset(slpm, 0xff, sizeof(slpm));
+
+ for (i = 0; i < num; i++) {
+ int pin = PIN_NUM(cfgs[i]);
+ int offset = pin % NMK_GPIO_PER_CHIP;
+
+ if (PIN_ALT(cfgs[i]) == NMK_GPIO_ALT_C)
+ slpm[pin / NMK_GPIO_PER_CHIP] &= ~BIT(offset);
+ }
+
+ nmk_gpio_glitch_slpm_init(slpm);
+ }
+
+ for (i = 0; i < num; i++) {
+ struct nmk_gpio_chip *nmk_chip;
+ int pin = PIN_NUM(cfgs[i]);
+
+ nmk_chip = irq_get_chip_data(NOMADIK_GPIO_TO_IRQ(pin));
+ if (!nmk_chip) {
+ ret = -EINVAL;
+ break;
+ }
+
+ spin_lock(&nmk_chip->lock);
+ __nmk_config_pin(nmk_chip, pin - nmk_chip->chip.base,
+ cfgs[i], sleep, glitch ? slpm : NULL);
+ spin_unlock(&nmk_chip->lock);
+ }
+
+ if (glitch)
+ nmk_gpio_glitch_slpm_restore(slpm);
+
+ spin_unlock_irqrestore(&nmk_gpio_slpm_lock, flags);
+
+ return ret;
+}
+
+/**
+ * nmk_config_pin - configure a pin's mux attributes
+ * @cfg: pin confguration
+ *
+ * Configures a pin's mode (alternate function or GPIO), its pull up status,
+ * and its sleep mode based on the specified configuration. The @cfg is
+ * usually one of the SoC specific macros defined in mach/<soc>-pins.h. These
+ * are constructed using, and can be further enhanced with, the macros in
+ * plat/pincfg.h.
+ *
+ * If a pin's mode is set to GPIO, it is configured as an input to avoid
+ * side-effects. The gpio can be manipulated later using standard GPIO API
+ * calls.
+ */
+int nmk_config_pin(pin_cfg_t cfg, bool sleep)
+{
+ return __nmk_config_pins(&cfg, 1, sleep);
+}
+EXPORT_SYMBOL(nmk_config_pin);
+
+/**
+ * nmk_config_pins - configure several pins at once
+ * @cfgs: array of pin configurations
+ * @num: number of elments in the array
+ *
+ * Configures several pins using nmk_config_pin(). Refer to that function for
+ * further information.
+ */
+int nmk_config_pins(pin_cfg_t *cfgs, int num)
+{
+ return __nmk_config_pins(cfgs, num, false);
+}
+EXPORT_SYMBOL(nmk_config_pins);
+
+int nmk_config_pins_sleep(pin_cfg_t *cfgs, int num)
+{
+ return __nmk_config_pins(cfgs, num, true);
+}
+EXPORT_SYMBOL(nmk_config_pins_sleep);
+
+/**
+ * nmk_gpio_set_slpm() - configure the sleep mode of a pin
+ * @gpio: pin number
+ * @mode: NMK_GPIO_SLPM_INPUT or NMK_GPIO_SLPM_NOCHANGE,
+ *
+ * Sets the sleep mode of a pin. If @mode is NMK_GPIO_SLPM_INPUT, the pin is
+ * changed to an input (with pullup/down enabled) in sleep and deep sleep. If
+ * @mode is NMK_GPIO_SLPM_NOCHANGE, the pin remains in the state it was
+ * configured even when in sleep and deep sleep.
+ *
+ * On DB8500v2 onwards, this setting loses the previous meaning and instead
+ * indicates if wakeup detection is enabled on the pin. Note that
+ * enable_irq_wake() will automatically enable wakeup detection.
+ */
+int nmk_gpio_set_slpm(int gpio, enum nmk_gpio_slpm mode)
+{
+ struct nmk_gpio_chip *nmk_chip;
+ unsigned long flags;
+
+ nmk_chip = irq_get_chip_data(NOMADIK_GPIO_TO_IRQ(gpio));
+ if (!nmk_chip)
+ return -EINVAL;
+
+ spin_lock_irqsave(&nmk_gpio_slpm_lock, flags);
+ spin_lock(&nmk_chip->lock);
+
+ __nmk_gpio_set_slpm(nmk_chip, gpio - nmk_chip->chip.base, mode);
+
+ spin_unlock(&nmk_chip->lock);
+ spin_unlock_irqrestore(&nmk_gpio_slpm_lock, flags);
+
+ return 0;
+}
+
+/**
+ * nmk_gpio_set_pull() - enable/disable pull up/down on a gpio
+ * @gpio: pin number
+ * @pull: one of NMK_GPIO_PULL_DOWN, NMK_GPIO_PULL_UP, and NMK_GPIO_PULL_NONE
+ *
+ * Enables/disables pull up/down on a specified pin. This only takes effect if
+ * the pin is configured as an input (either explicitly or by the alternate
+ * function).
+ *
+ * NOTE: If enabling the pull up/down, the caller must ensure that the GPIO is
+ * configured as an input. Otherwise, due to the way the controller registers
+ * work, this function will change the value output on the pin.
+ */
+int nmk_gpio_set_pull(int gpio, enum nmk_gpio_pull pull)
+{
+ struct nmk_gpio_chip *nmk_chip;
+ unsigned long flags;
+
+ nmk_chip = irq_get_chip_data(NOMADIK_GPIO_TO_IRQ(gpio));
+ if (!nmk_chip)
+ return -EINVAL;
+
+ spin_lock_irqsave(&nmk_chip->lock, flags);
+ __nmk_gpio_set_pull(nmk_chip, gpio - nmk_chip->chip.base, pull);
+ spin_unlock_irqrestore(&nmk_chip->lock, flags);
+
+ return 0;
+}
+
+/* Mode functions */
+/**
+ * nmk_gpio_set_mode() - set the mux mode of a gpio pin
+ * @gpio: pin number
+ * @gpio_mode: one of NMK_GPIO_ALT_GPIO, NMK_GPIO_ALT_A,
+ * NMK_GPIO_ALT_B, and NMK_GPIO_ALT_C
+ *
+ * Sets the mode of the specified pin to one of the alternate functions or
+ * plain GPIO.
+ */
+int nmk_gpio_set_mode(int gpio, int gpio_mode)
+{
+ struct nmk_gpio_chip *nmk_chip;
+ unsigned long flags;
+
+ nmk_chip = irq_get_chip_data(NOMADIK_GPIO_TO_IRQ(gpio));
+ if (!nmk_chip)
+ return -EINVAL;
+
+ spin_lock_irqsave(&nmk_chip->lock, flags);
+ __nmk_gpio_set_mode(nmk_chip, gpio - nmk_chip->chip.base, gpio_mode);
+ spin_unlock_irqrestore(&nmk_chip->lock, flags);
+
+ return 0;
+}
+EXPORT_SYMBOL(nmk_gpio_set_mode);
+
+int nmk_gpio_get_mode(int gpio)
+{
+ struct nmk_gpio_chip *nmk_chip;
+ u32 afunc, bfunc, bit;
+
+ nmk_chip = irq_get_chip_data(NOMADIK_GPIO_TO_IRQ(gpio));
+ if (!nmk_chip)
+ return -EINVAL;
+
+ bit = 1 << (gpio - nmk_chip->chip.base);
+
+ afunc = readl(nmk_chip->addr + NMK_GPIO_AFSLA) & bit;
+ bfunc = readl(nmk_chip->addr + NMK_GPIO_AFSLB) & bit;
+
+ return (afunc ? NMK_GPIO_ALT_A : 0) | (bfunc ? NMK_GPIO_ALT_B : 0);
+}
+EXPORT_SYMBOL(nmk_gpio_get_mode);
+
+
+/* IRQ functions */
+static inline int nmk_gpio_get_bitmask(int gpio)
+{
+ return 1 << (gpio % 32);
+}
+
+static void nmk_gpio_irq_ack(struct irq_data *d)
+{
+ int gpio;
+ struct nmk_gpio_chip *nmk_chip;
+
+ gpio = NOMADIK_IRQ_TO_GPIO(d->irq);
+ nmk_chip = irq_data_get_irq_chip_data(d);
+ if (!nmk_chip)
+ return;
+ writel(nmk_gpio_get_bitmask(gpio), nmk_chip->addr + NMK_GPIO_IC);
+}
+
+enum nmk_gpio_irq_type {
+ NORMAL,
+ WAKE,
+};
+
+static void __nmk_gpio_irq_modify(struct nmk_gpio_chip *nmk_chip,
+ int gpio, enum nmk_gpio_irq_type which,
+ bool enable)
+{
+ u32 rimsc = which == WAKE ? NMK_GPIO_RWIMSC : NMK_GPIO_RIMSC;
+ u32 fimsc = which == WAKE ? NMK_GPIO_FWIMSC : NMK_GPIO_FIMSC;
+ u32 bitmask = nmk_gpio_get_bitmask(gpio);
+ u32 reg;
+
+ /* we must individually set/clear the two edges */
+ if (nmk_chip->edge_rising & bitmask) {
+ reg = readl(nmk_chip->addr + rimsc);
+ if (enable)
+ reg |= bitmask;
+ else
+ reg &= ~bitmask;
+ writel(reg, nmk_chip->addr + rimsc);
+ }
+ if (nmk_chip->edge_falling & bitmask) {
+ reg = readl(nmk_chip->addr + fimsc);
+ if (enable)
+ reg |= bitmask;
+ else
+ reg &= ~bitmask;
+ writel(reg, nmk_chip->addr + fimsc);
+ }
+}
+
+static void __nmk_gpio_set_wake(struct nmk_gpio_chip *nmk_chip,
+ int gpio, bool on)
+{
+ __nmk_gpio_irq_modify(nmk_chip, gpio, WAKE, on);
+}
+
+static int nmk_gpio_irq_maskunmask(struct irq_data *d, bool enable)
+{
+ int gpio;
+ struct nmk_gpio_chip *nmk_chip;
+ unsigned long flags;
+ u32 bitmask;
+
+ gpio = NOMADIK_IRQ_TO_GPIO(d->irq);
+ nmk_chip = irq_data_get_irq_chip_data(d);
+ bitmask = nmk_gpio_get_bitmask(gpio);
+ if (!nmk_chip)
+ return -EINVAL;
+
+ if (enable)
+ nmk_chip->enabled |= bitmask;
+ else
+ nmk_chip->enabled &= ~bitmask;
+
+ spin_lock_irqsave(&nmk_gpio_slpm_lock, flags);
+ spin_lock(&nmk_chip->lock);
+
+ __nmk_gpio_irq_modify(nmk_chip, gpio, NORMAL, enable);
+
+ if (!(nmk_chip->real_wake & bitmask))
+ __nmk_gpio_set_wake(nmk_chip, gpio, enable);
+
+ spin_unlock(&nmk_chip->lock);
+ spin_unlock_irqrestore(&nmk_gpio_slpm_lock, flags);
+
+ return 0;
+}
+
+static void nmk_gpio_irq_mask(struct irq_data *d)
+{
+ nmk_gpio_irq_maskunmask(d, false);
+}
+
+static void nmk_gpio_irq_unmask(struct irq_data *d)
+{
+ nmk_gpio_irq_maskunmask(d, true);
+}
+
+static int nmk_gpio_irq_set_wake(struct irq_data *d, unsigned int on)
+{
+ struct nmk_gpio_chip *nmk_chip;
+ unsigned long flags;
+ u32 bitmask;
+ int gpio;
+
+ gpio = NOMADIK_IRQ_TO_GPIO(d->irq);
+ nmk_chip = irq_data_get_irq_chip_data(d);
+ if (!nmk_chip)
+ return -EINVAL;
+ bitmask = nmk_gpio_get_bitmask(gpio);
+
+ spin_lock_irqsave(&nmk_gpio_slpm_lock, flags);
+ spin_lock(&nmk_chip->lock);
+
+ if (!(nmk_chip->enabled & bitmask))
+ __nmk_gpio_set_wake(nmk_chip, gpio, on);
+
+ if (on)
+ nmk_chip->real_wake |= bitmask;
+ else
+ nmk_chip->real_wake &= ~bitmask;
+
+ spin_unlock(&nmk_chip->lock);
+ spin_unlock_irqrestore(&nmk_gpio_slpm_lock, flags);
+
+ return 0;
+}
+
+static int nmk_gpio_irq_set_type(struct irq_data *d, unsigned int type)
+{
+ bool enabled, wake = irqd_is_wakeup_set(d);
+ int gpio;
+ struct nmk_gpio_chip *nmk_chip;
+ unsigned long flags;
+ u32 bitmask;
+
+ gpio = NOMADIK_IRQ_TO_GPIO(d->irq);
+ nmk_chip = irq_data_get_irq_chip_data(d);
+ bitmask = nmk_gpio_get_bitmask(gpio);
+ if (!nmk_chip)
+ return -EINVAL;
+
+ if (type & IRQ_TYPE_LEVEL_HIGH)
+ return -EINVAL;
+ if (type & IRQ_TYPE_LEVEL_LOW)
+ return -EINVAL;
+
+ enabled = nmk_chip->enabled & bitmask;
+
+ spin_lock_irqsave(&nmk_chip->lock, flags);
+
+ if (enabled)
+ __nmk_gpio_irq_modify(nmk_chip, gpio, NORMAL, false);
+
+ if (enabled || wake)
+ __nmk_gpio_irq_modify(nmk_chip, gpio, WAKE, false);
+
+ nmk_chip->edge_rising &= ~bitmask;
+ if (type & IRQ_TYPE_EDGE_RISING)
+ nmk_chip->edge_rising |= bitmask;
+
+ nmk_chip->edge_falling &= ~bitmask;
+ if (type & IRQ_TYPE_EDGE_FALLING)
+ nmk_chip->edge_falling |= bitmask;
+
+ if (enabled)
+ __nmk_gpio_irq_modify(nmk_chip, gpio, NORMAL, true);
+
+ if (enabled || wake)
+ __nmk_gpio_irq_modify(nmk_chip, gpio, WAKE, true);
+
+ spin_unlock_irqrestore(&nmk_chip->lock, flags);
+
+ return 0;
+}
+
+static struct irq_chip nmk_gpio_irq_chip = {
+ .name = "Nomadik-GPIO",
+ .irq_ack = nmk_gpio_irq_ack,
+ .irq_mask = nmk_gpio_irq_mask,
+ .irq_unmask = nmk_gpio_irq_unmask,
+ .irq_set_type = nmk_gpio_irq_set_type,
+ .irq_set_wake = nmk_gpio_irq_set_wake,
+};
+
+static void __nmk_gpio_irq_handler(unsigned int irq, struct irq_desc *desc,
+ u32 status)
+{
+ struct nmk_gpio_chip *nmk_chip;
+ struct irq_chip *host_chip = irq_get_chip(irq);
+ unsigned int first_irq;
+
+ chained_irq_enter(host_chip, desc);
+
+ nmk_chip = irq_get_handler_data(irq);
+ first_irq = NOMADIK_GPIO_TO_IRQ(nmk_chip->chip.base);
+ while (status) {
+ int bit = __ffs(status);
+
+ generic_handle_irq(first_irq + bit);
+ status &= ~BIT(bit);
+ }
+
+ chained_irq_exit(host_chip, desc);
+}
+
+static void nmk_gpio_irq_handler(unsigned int irq, struct irq_desc *desc)
+{
+ struct nmk_gpio_chip *nmk_chip = irq_get_handler_data(irq);
+ u32 status = readl(nmk_chip->addr + NMK_GPIO_IS);
+
+ __nmk_gpio_irq_handler(irq, desc, status);
+}
+
+static void nmk_gpio_secondary_irq_handler(unsigned int irq,
+ struct irq_desc *desc)
+{
+ struct nmk_gpio_chip *nmk_chip = irq_get_handler_data(irq);
+ u32 status = nmk_chip->get_secondary_status(nmk_chip->bank);
+
+ __nmk_gpio_irq_handler(irq, desc, status);
+}
+
+static int nmk_gpio_init_irq(struct nmk_gpio_chip *nmk_chip)
+{
+ unsigned int first_irq;
+ int i;
+
+ first_irq = NOMADIK_GPIO_TO_IRQ(nmk_chip->chip.base);
+ for (i = first_irq; i < first_irq + nmk_chip->chip.ngpio; i++) {
+ irq_set_chip_and_handler(i, &nmk_gpio_irq_chip,
+ handle_edge_irq);
+ set_irq_flags(i, IRQF_VALID);
+ irq_set_chip_data(i, nmk_chip);
+ irq_set_irq_type(i, IRQ_TYPE_EDGE_FALLING);
+ }
+
+ irq_set_chained_handler(nmk_chip->parent_irq, nmk_gpio_irq_handler);
+ irq_set_handler_data(nmk_chip->parent_irq, nmk_chip);
+
+ if (nmk_chip->secondary_parent_irq >= 0) {
+ irq_set_chained_handler(nmk_chip->secondary_parent_irq,
+ nmk_gpio_secondary_irq_handler);
+ irq_set_handler_data(nmk_chip->secondary_parent_irq, nmk_chip);
+ }
+
+ return 0;
+}
+
+/* I/O Functions */
+static int nmk_gpio_make_input(struct gpio_chip *chip, unsigned offset)
+{
+ struct nmk_gpio_chip *nmk_chip =
+ container_of(chip, struct nmk_gpio_chip, chip);
+
+ writel(1 << offset, nmk_chip->addr + NMK_GPIO_DIRC);
+ return 0;
+}
+
+static int nmk_gpio_get_input(struct gpio_chip *chip, unsigned offset)
+{
+ struct nmk_gpio_chip *nmk_chip =
+ container_of(chip, struct nmk_gpio_chip, chip);
+ u32 bit = 1 << offset;
+
+ return (readl(nmk_chip->addr + NMK_GPIO_DAT) & bit) != 0;
+}
+
+static void nmk_gpio_set_output(struct gpio_chip *chip, unsigned offset,
+ int val)
+{
+ struct nmk_gpio_chip *nmk_chip =
+ container_of(chip, struct nmk_gpio_chip, chip);
+
+ __nmk_gpio_set_output(nmk_chip, offset, val);
+}
+
+static int nmk_gpio_make_output(struct gpio_chip *chip, unsigned offset,
+ int val)
+{
+ struct nmk_gpio_chip *nmk_chip =
+ container_of(chip, struct nmk_gpio_chip, chip);
+
+ __nmk_gpio_make_output(nmk_chip, offset, val);
+
+ return 0;
+}
+
+static int nmk_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
+{
+ struct nmk_gpio_chip *nmk_chip =
+ container_of(chip, struct nmk_gpio_chip, chip);
+
+ return NOMADIK_GPIO_TO_IRQ(nmk_chip->chip.base) + offset;
+}
+
+#ifdef CONFIG_DEBUG_FS
+
+#include <linux/seq_file.h>
+
+static void nmk_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
+{
+ int mode;
+ unsigned i;
+ unsigned gpio = chip->base;
+ int is_out;
+ struct nmk_gpio_chip *nmk_chip =
+ container_of(chip, struct nmk_gpio_chip, chip);
+ const char *modes[] = {
+ [NMK_GPIO_ALT_GPIO] = "gpio",
+ [NMK_GPIO_ALT_A] = "altA",
+ [NMK_GPIO_ALT_B] = "altB",
+ [NMK_GPIO_ALT_C] = "altC",
+ };
+
+ for (i = 0; i < chip->ngpio; i++, gpio++) {
+ const char *label = gpiochip_is_requested(chip, i);
+ bool pull;
+ u32 bit = 1 << i;
+
+ is_out = readl(nmk_chip->addr + NMK_GPIO_DIR) & bit;
+ pull = !(readl(nmk_chip->addr + NMK_GPIO_PDIS) & bit);
+ mode = nmk_gpio_get_mode(gpio);
+ seq_printf(s, " gpio-%-3d (%-20.20s) %s %s %s %s",
+ gpio, label ?: "(none)",
+ is_out ? "out" : "in ",
+ chip->get
+ ? (chip->get(chip, i) ? "hi" : "lo")
+ : "? ",
+ (mode < 0) ? "unknown" : modes[mode],
+ pull ? "pull" : "none");
+
+ if (label && !is_out) {
+ int irq = gpio_to_irq(gpio);
+ struct irq_desc *desc = irq_to_desc(irq);
+
+ /* This races with request_irq(), set_irq_type(),
+ * and set_irq_wake() ... but those are "rare".
+ */
+ if (irq >= 0 && desc->action) {
+ char *trigger;
+ u32 bitmask = nmk_gpio_get_bitmask(gpio);
+
+ if (nmk_chip->edge_rising & bitmask)
+ trigger = "edge-rising";
+ else if (nmk_chip->edge_falling & bitmask)
+ trigger = "edge-falling";
+ else
+ trigger = "edge-undefined";
+
+ seq_printf(s, " irq-%d %s%s",
+ irq, trigger,
+ irqd_is_wakeup_set(&desc->irq_data)
+ ? " wakeup" : "");
+ }
+ }
+
+ seq_printf(s, "\n");
+ }
+}
+
+#else
+#define nmk_gpio_dbg_show NULL
+#endif
+
+/* This structure is replicated for each GPIO block allocated at probe time */
+static struct gpio_chip nmk_gpio_template = {
+ .direction_input = nmk_gpio_make_input,
+ .get = nmk_gpio_get_input,
+ .direction_output = nmk_gpio_make_output,
+ .set = nmk_gpio_set_output,
+ .to_irq = nmk_gpio_to_irq,
+ .dbg_show = nmk_gpio_dbg_show,
+ .can_sleep = 0,
+};
+
+/*
+ * Called from the suspend/resume path to only keep the real wakeup interrupts
+ * (those that have had set_irq_wake() called on them) as wakeup interrupts,
+ * and not the rest of the interrupts which we needed to have as wakeups for
+ * cpuidle.
+ *
+ * PM ops are not used since this needs to be done at the end, after all the
+ * other drivers are done with their suspend callbacks.
+ */
+void nmk_gpio_wakeups_suspend(void)
+{
+ int i;
+
+ for (i = 0; i < NUM_BANKS; i++) {
+ struct nmk_gpio_chip *chip = nmk_gpio_chips[i];
+
+ if (!chip)
+ break;
+
+ chip->rwimsc = readl(chip->addr + NMK_GPIO_RWIMSC);
+ chip->fwimsc = readl(chip->addr + NMK_GPIO_FWIMSC);
+
+ writel(chip->rwimsc & chip->real_wake,
+ chip->addr + NMK_GPIO_RWIMSC);
+ writel(chip->fwimsc & chip->real_wake,
+ chip->addr + NMK_GPIO_FWIMSC);
+
+ if (cpu_is_u8500v2()) {
+ chip->slpm = readl(chip->addr + NMK_GPIO_SLPC);
+
+ /* 0 -> wakeup enable */
+ writel(~chip->real_wake, chip->addr + NMK_GPIO_SLPC);
+ }
+ }
+}
+
+void nmk_gpio_wakeups_resume(void)
+{
+ int i;
+
+ for (i = 0; i < NUM_BANKS; i++) {
+ struct nmk_gpio_chip *chip = nmk_gpio_chips[i];
+
+ if (!chip)
+ break;
+
+ writel(chip->rwimsc, chip->addr + NMK_GPIO_RWIMSC);
+ writel(chip->fwimsc, chip->addr + NMK_GPIO_FWIMSC);
+
+ if (cpu_is_u8500v2())
+ writel(chip->slpm, chip->addr + NMK_GPIO_SLPC);
+ }
+}
+
+/*
+ * Read the pull up/pull down status.
+ * A bit set in 'pull_up' means that pull up
+ * is selected if pull is enabled in PDIS register.
+ * Note: only pull up/down set via this driver can
+ * be detected due to HW limitations.
+ */
+void nmk_gpio_read_pull(int gpio_bank, u32 *pull_up)
+{
+ if (gpio_bank < NUM_BANKS) {
+ struct nmk_gpio_chip *chip = nmk_gpio_chips[gpio_bank];
+
+ if (!chip)
+ return;
+
+ *pull_up = chip->pull_up;
+ }
+}
+
+static int __devinit nmk_gpio_probe(struct platform_device *dev)
+{
+ struct nmk_gpio_platform_data *pdata = dev->dev.platform_data;
+ struct nmk_gpio_chip *nmk_chip;
+ struct gpio_chip *chip;
+ struct resource *res;
+ struct clk *clk;
+ int secondary_irq;
+ int irq;
+ int ret;
+
+ if (!pdata)
+ return -ENODEV;
+
+ res = platform_get_resource(dev, IORESOURCE_MEM, 0);
+ if (!res) {
+ ret = -ENOENT;
+ goto out;
+ }
+
+ irq = platform_get_irq(dev, 0);
+ if (irq < 0) {
+ ret = irq;
+ goto out;
+ }
+
+ secondary_irq = platform_get_irq(dev, 1);
+ if (secondary_irq >= 0 && !pdata->get_secondary_status) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ if (request_mem_region(res->start, resource_size(res),
+ dev_name(&dev->dev)) == NULL) {
+ ret = -EBUSY;
+ goto out;
+ }
+
+ clk = clk_get(&dev->dev, NULL);
+ if (IS_ERR(clk)) {
+ ret = PTR_ERR(clk);
+ goto out_release;
+ }
+
+ clk_enable(clk);
+
+ nmk_chip = kzalloc(sizeof(*nmk_chip), GFP_KERNEL);
+ if (!nmk_chip) {
+ ret = -ENOMEM;
+ goto out_clk;
+ }
+ /*
+ * The virt address in nmk_chip->addr is in the nomadik register space,
+ * so we can simply convert the resource address, without remapping
+ */
+ nmk_chip->bank = dev->id;
+ nmk_chip->clk = clk;
+ nmk_chip->addr = io_p2v(res->start);
+ nmk_chip->chip = nmk_gpio_template;
+ nmk_chip->parent_irq = irq;
+ nmk_chip->secondary_parent_irq = secondary_irq;
+ nmk_chip->get_secondary_status = pdata->get_secondary_status;
+ nmk_chip->set_ioforce = pdata->set_ioforce;
+ spin_lock_init(&nmk_chip->lock);
+
+ chip = &nmk_chip->chip;
+ chip->base = pdata->first_gpio;
+ chip->ngpio = pdata->num_gpio;
+ chip->label = pdata->name ?: dev_name(&dev->dev);
+ chip->dev = &dev->dev;
+ chip->owner = THIS_MODULE;
+
+ ret = gpiochip_add(&nmk_chip->chip);
+ if (ret)
+ goto out_free;
+
+ BUG_ON(nmk_chip->bank >= ARRAY_SIZE(nmk_gpio_chips));
+
+ nmk_gpio_chips[nmk_chip->bank] = nmk_chip;
+ platform_set_drvdata(dev, nmk_chip);
+
+ nmk_gpio_init_irq(nmk_chip);
+
+ dev_info(&dev->dev, "Bits %i-%i at address %p\n",
+ nmk_chip->chip.base, nmk_chip->chip.base+31, nmk_chip->addr);
+ return 0;
+
+out_free:
+ kfree(nmk_chip);
+out_clk:
+ clk_disable(clk);
+ clk_put(clk);
+out_release:
+ release_mem_region(res->start, resource_size(res));
+out:
+ dev_err(&dev->dev, "Failure %i for GPIO %i-%i\n", ret,
+ pdata->first_gpio, pdata->first_gpio+31);
+ return ret;
+}
+
+static struct platform_driver nmk_gpio_driver = {
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = "gpio",
+ },
+ .probe = nmk_gpio_probe,
+};
+
+static int __init nmk_gpio_init(void)
+{
+ return platform_driver_register(&nmk_gpio_driver);
+}
+
+core_initcall(nmk_gpio_init);
+
+MODULE_AUTHOR("Prafulla WADASKAR and Alessandro Rubini");
+MODULE_DESCRIPTION("Nomadik GPIO Driver");
+MODULE_LICENSE("GPL");
+
+
OpenPOWER on IntegriCloud