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-rw-r--r--arch/arm/plat-s3c/Makefile1
-rw-r--r--arch/arm/plat-s3c/gpio.c11
-rw-r--r--arch/arm/plat-s3c/include/plat/gpio-core.h30
-rw-r--r--arch/arm/plat-s3c/pm-gpio.c380
4 files changed, 421 insertions, 1 deletions
diff --git a/arch/arm/plat-s3c/Makefile b/arch/arm/plat-s3c/Makefile
index aa995a4..bfc8f53 100644
--- a/arch/arm/plat-s3c/Makefile
+++ b/arch/arm/plat-s3c/Makefile
@@ -21,6 +21,7 @@ obj-y += gpio-config.o
# PM support
obj-$(CONFIG_PM) += pm.o
+obj-$(CONFIG_PM) += pm-gpio.o
obj-$(CONFIG_S3C2410_PM_CHECK) += pm-check.o
# devices
diff --git a/arch/arm/plat-s3c/gpio.c b/arch/arm/plat-s3c/gpio.c
index d71dd6d..260fdc6 100644
--- a/arch/arm/plat-s3c/gpio.c
+++ b/arch/arm/plat-s3c/gpio.c
@@ -16,7 +16,7 @@
#include <linux/io.h>
#include <linux/gpio.h>
-#include <plat/gpio-core.h>
+#include <mach/gpio-core.h>
#ifdef CONFIG_S3C_GPIO_TRACK
struct s3c_gpio_chip *s3c_gpios[S3C_GPIO_END];
@@ -140,6 +140,15 @@ __init void s3c_gpiolib_add(struct s3c_gpio_chip *chip)
if (!gc->get)
gc->get = s3c_gpiolib_get;
+#ifdef CONFIG_PM
+ if (chip->pm != NULL) {
+ if (!chip->pm->save || !chip->pm->resume)
+ printk(KERN_ERR "gpio: %s has missing PM functions\n",
+ gc->label);
+ } else
+ printk(KERN_ERR "gpio: %s has no PM function\n", gc->label);
+#endif
+
/* gpiochip_add() prints own failure message on error. */
ret = gpiochip_add(gc);
if (ret >= 0)
diff --git a/arch/arm/plat-s3c/include/plat/gpio-core.h b/arch/arm/plat-s3c/include/plat/gpio-core.h
index 2fc60a5..32af612 100644
--- a/arch/arm/plat-s3c/include/plat/gpio-core.h
+++ b/arch/arm/plat-s3c/include/plat/gpio-core.h
@@ -20,6 +20,18 @@
* specific code.
*/
+struct s3c_gpio_chip;
+
+/**
+ * struct s3c_gpio_pm - power management (suspend/resume) information
+ * @save: Routine to save the state of the GPIO block
+ * @resume: Routine to resume the GPIO block.
+ */
+struct s3c_gpio_pm {
+ void (*save)(struct s3c_gpio_chip *chip);
+ void (*resume)(struct s3c_gpio_chip *chip);
+};
+
struct s3c_gpio_cfg;
/**
@@ -27,6 +39,7 @@ struct s3c_gpio_cfg;
* @chip: The chip structure to be exported via gpiolib.
* @base: The base pointer to the gpio configuration registers.
* @config: special function and pull-resistor control information.
+ * @pm_save: Save information for suspend/resume support.
*
* This wrapper provides the necessary information for the Samsung
* specific gpios being registered with gpiolib.
@@ -34,7 +47,11 @@ struct s3c_gpio_cfg;
struct s3c_gpio_chip {
struct gpio_chip chip;
struct s3c_gpio_cfg *config;
+ struct s3c_gpio_pm *pm;
void __iomem *base;
+#ifdef CONFIG_PM
+ u32 pm_save[4];
+#endif
};
static inline struct s3c_gpio_chip *to_s3c_gpio(struct gpio_chip *gpc)
@@ -75,3 +92,16 @@ static inline struct s3c_gpio_chip *s3c_gpiolib_getchip(unsigned int chip)
static inline void s3c_gpiolib_track(struct s3c_gpio_chip *chip) { }
#endif
+
+#ifdef CONFIG_PM
+extern struct s3c_gpio_pm s3c_gpio_pm_1bit;
+extern struct s3c_gpio_pm s3c_gpio_pm_2bit;
+extern struct s3c_gpio_pm s3c_gpio_pm_4bit;
+#define __gpio_pm(x) x
+#else
+#define s3c_gpio_pm_1bit NULL
+#define s3c_gpio_pm_2bit NULL
+#define s3c_gpio_pm_4bit NULL
+#define __gpio_pm(x) NULL
+
+#endif /* CONFIG_PM */
diff --git a/arch/arm/plat-s3c/pm-gpio.c b/arch/arm/plat-s3c/pm-gpio.c
new file mode 100644
index 0000000..cfd326a
--- /dev/null
+++ b/arch/arm/plat-s3c/pm-gpio.c
@@ -0,0 +1,380 @@
+
+/* linux/arch/arm/plat-s3c/pm-gpio.c
+ *
+ * Copyright 2008 Openmoko, Inc.
+ * Copyright 2008 Simtec Electronics
+ * Ben Dooks <ben@simtec.co.uk>
+ * http://armlinux.simtec.co.uk/
+ *
+ * S3C series GPIO PM code
+ *
+ * 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/sysdev.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/gpio.h>
+
+#include <mach/gpio-core.h>
+#include <plat/pm.h>
+
+/* PM GPIO helpers */
+
+#define OFFS_CON (0x00)
+#define OFFS_DAT (0x04)
+#define OFFS_UP (0x08)
+
+static void s3c_gpio_pm_1bit_save(struct s3c_gpio_chip *chip)
+{
+ chip->pm_save[0] = __raw_readl(chip->base + OFFS_CON);
+ chip->pm_save[1] = __raw_readl(chip->base + OFFS_DAT);
+}
+
+static void s3c_gpio_pm_1bit_resume(struct s3c_gpio_chip *chip)
+{
+ void __iomem *base = chip->base;
+ u32 old_gpcon = __raw_readl(base + OFFS_CON);
+ u32 old_gpdat = __raw_readl(base + OFFS_DAT);
+ u32 gps_gpcon = chip->pm_save[0];
+ u32 gps_gpdat = chip->pm_save[1];
+ u32 gpcon;
+
+ /* GPACON only has one bit per control / data and no PULLUPs.
+ * GPACON[x] = 0 => Output, 1 => SFN */
+
+ /* first set all SFN bits to SFN */
+
+ gpcon = old_gpcon | gps_gpcon;
+ __raw_writel(gpcon, base + OFFS_CON);
+
+ /* now set all the other bits */
+
+ __raw_writel(gps_gpdat, base + OFFS_DAT);
+ __raw_writel(gps_gpcon, base + OFFS_CON);
+
+ S3C_PMDBG("%s: CON %08x => %08x, DAT %08x => %08x\n",
+ chip->chip.label, old_gpcon, gps_gpcon, old_gpdat, gps_gpdat);
+}
+
+struct s3c_gpio_pm s3c_gpio_pm_1bit = {
+ .save = s3c_gpio_pm_1bit_save,
+ .resume = s3c_gpio_pm_1bit_resume,
+};
+
+static void s3c_gpio_pm_2bit_save(struct s3c_gpio_chip *chip)
+{
+ chip->pm_save[0] = __raw_readl(chip->base + OFFS_CON);
+ chip->pm_save[1] = __raw_readl(chip->base + OFFS_DAT);
+ chip->pm_save[2] = __raw_readl(chip->base + OFFS_UP);
+}
+
+/* Test whether the given masked+shifted bits of an GPIO configuration
+ * are one of the SFN (special function) modes. */
+
+static inline int is_sfn(unsigned long con)
+{
+ return con >= 2;
+}
+
+/* Test if the given masked+shifted GPIO configuration is an input */
+
+static inline int is_in(unsigned long con)
+{
+ return con == 0;
+}
+
+/* Test if the given masked+shifted GPIO configuration is an output */
+
+static inline int is_out(unsigned long con)
+{
+ return con == 1;
+}
+
+/**
+ * s3c_gpio_pm_2bit_resume() - restore the given GPIO bank
+ * @chip: The chip information to resume.
+ *
+ * Restore one of the GPIO banks that was saved during suspend. This is
+ * not as simple as once thought, due to the possibility of glitches
+ * from the order that the CON and DAT registers are set in.
+ *
+ * The three states the pin can be are {IN,OUT,SFN} which gives us 9
+ * combinations of changes to check. Three of these, if the pin stays
+ * in the same configuration can be discounted. This leaves us with
+ * the following:
+ *
+ * { IN => OUT } Change DAT first
+ * { IN => SFN } Change CON first
+ * { OUT => SFN } Change CON first, so new data will not glitch
+ * { OUT => IN } Change CON first, so new data will not glitch
+ * { SFN => IN } Change CON first
+ * { SFN => OUT } Change DAT first, so new data will not glitch [1]
+ *
+ * We do not currently deal with the UP registers as these control
+ * weak resistors, so a small delay in change should not need to bring
+ * these into the calculations.
+ *
+ * [1] this assumes that writing to a pin DAT whilst in SFN will set the
+ * state for when it is next output.
+ */
+static void s3c_gpio_pm_2bit_resume(struct s3c_gpio_chip *chip)
+{
+ void __iomem *base = chip->base;
+ u32 old_gpcon = __raw_readl(base + OFFS_CON);
+ u32 old_gpdat = __raw_readl(base + OFFS_DAT);
+ u32 gps_gpcon = chip->pm_save[0];
+ u32 gps_gpdat = chip->pm_save[1];
+ u32 gpcon, old, new, mask;
+ u32 change_mask = 0x0;
+ int nr;
+
+ /* restore GPIO pull-up settings */
+ __raw_writel(chip->pm_save[2], base + OFFS_UP);
+
+ /* Create a change_mask of all the items that need to have
+ * their CON value changed before their DAT value, so that
+ * we minimise the work between the two settings.
+ */
+
+ for (nr = 0, mask = 0x03; nr < 32; nr += 2, mask <<= 2) {
+ old = (old_gpcon & mask) >> nr;
+ new = (gps_gpcon & mask) >> nr;
+
+ /* If there is no change, then skip */
+
+ if (old == new)
+ continue;
+
+ /* If both are special function, then skip */
+
+ if (is_sfn(old) && is_sfn(new))
+ continue;
+
+ /* Change is IN => OUT, do not change now */
+
+ if (is_in(old) && is_out(new))
+ continue;
+
+ /* Change is SFN => OUT, do not change now */
+
+ if (is_sfn(old) && is_out(new))
+ continue;
+
+ /* We should now be at the case of IN=>SFN,
+ * OUT=>SFN, OUT=>IN, SFN=>IN. */
+
+ change_mask |= mask;
+ }
+
+
+ /* Write the new CON settings */
+
+ gpcon = old_gpcon & ~change_mask;
+ gpcon |= gps_gpcon & change_mask;
+
+ __raw_writel(gpcon, base + OFFS_CON);
+
+ /* Now change any items that require DAT,CON */
+
+ __raw_writel(gps_gpdat, base + OFFS_DAT);
+ __raw_writel(gps_gpcon, base + OFFS_CON);
+
+ S3C_PMDBG("%s: CON %08x => %08x, DAT %08x => %08x\n",
+ chip->chip.label, old_gpcon, gps_gpcon, old_gpdat, gps_gpdat);
+}
+
+struct s3c_gpio_pm s3c_gpio_pm_2bit = {
+ .save = s3c_gpio_pm_2bit_save,
+ .resume = s3c_gpio_pm_2bit_resume,
+};
+
+#ifdef CONFIG_ARCH_S3C64XX
+static void s3c_gpio_pm_4bit_save(struct s3c_gpio_chip *chip)
+{
+ chip->pm_save[1] = __raw_readl(chip->base + OFFS_CON);
+ chip->pm_save[2] = __raw_readl(chip->base + OFFS_DAT);
+ chip->pm_save[3] = __raw_readl(chip->base + OFFS_UP);
+
+ if (chip->chip.ngpio > 8)
+ chip->pm_save[0] = __raw_readl(chip->base - 4);
+}
+
+static u32 s3c_gpio_pm_4bit_mask(u32 old_gpcon, u32 gps_gpcon)
+{
+ u32 old, new, mask;
+ u32 change_mask = 0x0;
+ int nr;
+
+ for (nr = 0, mask = 0x0f; nr < 16; nr += 4, mask <<= 4) {
+ old = (old_gpcon & mask) >> nr;
+ new = (gps_gpcon & mask) >> nr;
+
+ /* If there is no change, then skip */
+
+ if (old == new)
+ continue;
+
+ /* If both are special function, then skip */
+
+ if (is_sfn(old) && is_sfn(new))
+ continue;
+
+ /* Change is IN => OUT, do not change now */
+
+ if (is_in(old) && is_out(new))
+ continue;
+
+ /* Change is SFN => OUT, do not change now */
+
+ if (is_sfn(old) && is_out(new))
+ continue;
+
+ /* We should now be at the case of IN=>SFN,
+ * OUT=>SFN, OUT=>IN, SFN=>IN. */
+
+ change_mask |= mask;
+ }
+
+ return change_mask;
+}
+
+static void s3c_gpio_pm_4bit_con(struct s3c_gpio_chip *chip, int index)
+{
+ void __iomem *con = chip->base + (index * 4);
+ u32 old_gpcon = __raw_readl(con);
+ u32 gps_gpcon = chip->pm_save[index + 1];
+ u32 gpcon, mask;
+
+ mask = s3c_gpio_pm_4bit_mask(old_gpcon, gps_gpcon);
+
+ gpcon = old_gpcon & ~mask;
+ gpcon |= gps_gpcon & mask;
+
+ __raw_writel(gpcon, con);
+}
+
+static void s3c_gpio_pm_4bit_resume(struct s3c_gpio_chip *chip)
+{
+ void __iomem *base = chip->base;
+ u32 old_gpcon[2];
+ u32 old_gpdat = __raw_readl(base + OFFS_DAT);
+ u32 gps_gpdat = chip->pm_save[2];
+
+ /* First, modify the CON settings */
+
+ old_gpcon[0] = 0;
+ old_gpcon[1] = __raw_readl(base + OFFS_CON);
+
+ s3c_gpio_pm_4bit_con(chip, 0);
+ if (chip->chip.ngpio > 8) {
+ old_gpcon[0] = __raw_readl(base - 4);
+ s3c_gpio_pm_4bit_con(chip, -1);
+ }
+
+ /* Now change the configurations that require DAT,CON */
+
+ __raw_writel(chip->pm_save[2], base + OFFS_DAT);
+ __raw_writel(chip->pm_save[1], base + OFFS_CON);
+ if (chip->chip.ngpio > 8)
+ __raw_writel(chip->pm_save[0], base - 4);
+
+ __raw_writel(chip->pm_save[2], base + OFFS_DAT);
+ __raw_writel(chip->pm_save[3], base + OFFS_UP);
+
+ if (chip->chip.ngpio > 8) {
+ S3C_PMDBG("%s: CON4 %08x,%08x => %08x,%08x, DAT %08x => %08x\n",
+ chip->chip.label, old_gpcon[0], old_gpcon[1],
+ __raw_readl(base - 4),
+ __raw_readl(base + OFFS_CON),
+ old_gpdat, gps_gpdat);
+ } else
+ S3C_PMDBG("%s: CON4 %08x => %08x, DAT %08x => %08x\n",
+ chip->chip.label, old_gpcon[1],
+ __raw_readl(base + OFFS_CON),
+ old_gpdat, gps_gpdat);
+}
+
+struct s3c_gpio_pm s3c_gpio_pm_4bit = {
+ .save = s3c_gpio_pm_4bit_save,
+ .resume = s3c_gpio_pm_4bit_resume,
+};
+#endif /* CONFIG_ARCH_S3C64XX */
+
+/**
+ * s3c_pm_save_gpio() - save gpio chip data for suspend
+ * @ourchip: The chip for suspend.
+ */
+static void s3c_pm_save_gpio(struct s3c_gpio_chip *ourchip)
+{
+ struct s3c_gpio_pm *pm = ourchip->pm;
+
+ if (pm == NULL || pm->save == NULL)
+ S3C_PMDBG("%s: no pm for %s\n", __func__, ourchip->chip.label);
+ else
+ pm->save(ourchip);
+}
+
+/**
+ * s3c_pm_save_gpios() - Save the state of the GPIO banks.
+ *
+ * For all the GPIO banks, save the state of each one ready for going
+ * into a suspend mode.
+ */
+void s3c_pm_save_gpios(void)
+{
+ struct s3c_gpio_chip *ourchip;
+ unsigned int gpio_nr;
+
+ for (gpio_nr = 0; gpio_nr < S3C_GPIO_END; gpio_nr++) {
+ ourchip = s3c_gpiolib_getchip(gpio_nr);
+ if (!ourchip)
+ continue;
+
+ s3c_pm_save_gpio(ourchip);
+
+ S3C_PMDBG("%s: save %08x,%08x,%08x,%08x\n",
+ ourchip->chip.label,
+ ourchip->pm_save[0],
+ ourchip->pm_save[1],
+ ourchip->pm_save[2],
+ ourchip->pm_save[3]);
+
+ gpio_nr += ourchip->chip.ngpio;
+ gpio_nr += CONFIG_S3C_GPIO_SPACE;
+ }
+}
+
+/**
+ * s3c_pm_resume_gpio() - restore gpio chip data after suspend
+ * @ourchip: The suspended chip.
+ */
+static void s3c_pm_resume_gpio(struct s3c_gpio_chip *ourchip)
+{
+ struct s3c_gpio_pm *pm = ourchip->pm;
+
+ if (pm == NULL || pm->resume == NULL)
+ S3C_PMDBG("%s: no pm for %s\n", __func__, ourchip->chip.label);
+ else
+ pm->resume(ourchip);
+}
+
+void s3c_pm_restore_gpios(void)
+{
+ struct s3c_gpio_chip *ourchip;
+ unsigned int gpio_nr;
+
+ for (gpio_nr = 0; gpio_nr < S3C_GPIO_END; gpio_nr++) {
+ ourchip = s3c_gpiolib_getchip(gpio_nr);
+ if (!ourchip)
+ continue;
+
+ s3c_pm_resume_gpio(ourchip);
+
+ gpio_nr += ourchip->chip.ngpio;
+ gpio_nr += CONFIG_S3C_GPIO_SPACE;
+ }
+}
generated by cgit v1.1 at 2024-12-28 02:57:14 +0000