[patch 2/4] SM501: Add gpiolib support

From: Ben Dooks
Date: Sun Jun 22 2008 - 17:15:49 EST


Add support for exporting the GPIOs on the SM501
via gpiolib.

Signed-off-by: Ben Dooks <ben-linux@xxxxxxxxx>

Index: linux-2.6.26-rc5-quilt1/include/linux/sm501.h
===================================================================
--- linux-2.6.26-rc5-quilt1.orig/include/linux/sm501.h 2008-06-11 11:29:03.000000000 +0100
+++ linux-2.6.26-rc5-quilt1/include/linux/sm501.h 2008-06-11 11:29:03.000000000 +0100
@@ -46,24 +46,6 @@ extern unsigned long sm501_modify_reg(st
unsigned long set,
unsigned long clear);

-/* sm501_gpio_set
- *
- * set the state of the given GPIO line
-*/
-
-extern void sm501_gpio_set(struct device *dev,
- unsigned long gpio,
- unsigned int to,
- unsigned int dir);
-
-/* sm501_gpio_get
- *
- * get the state of the given GPIO line
-*/
-
-extern unsigned long sm501_gpio_get(struct device *dev,
- unsigned long gpio);
-

/* Platform data definitions */

@@ -131,6 +113,7 @@ struct sm501_reg_init {
#define SM501_USE_FBACCEL (1<<6)
#define SM501_USE_AC97 (1<<7)
#define SM501_USE_I2S (1<<8)
+#define SM501_USE_GPIO (1<<9)

#define SM501_USE_ALL (0xffffffff)

@@ -173,6 +156,7 @@ struct sm501_platdata {
struct sm501_platdata_fb *fb;

int flags;
+ unsigned gpio_base;

int (*get_power)(struct device *dev);
int (*set_power)(struct device *dev, unsigned int on);
Index: linux-2.6.26-rc5-quilt1/drivers/mfd/sm501.c
===================================================================
--- linux-2.6.26-rc5-quilt1.orig/drivers/mfd/sm501.c 2008-06-11 11:29:03.000000000 +0100
+++ linux-2.6.26-rc5-quilt1/drivers/mfd/sm501.c 2008-06-11 11:31:57.000000000 +0100
@@ -19,6 +19,7 @@
#include <linux/device.h>
#include <linux/platform_device.h>
#include <linux/pci.h>
+#include <linux/gpio.h>

#include <linux/sm501.h>
#include <linux/sm501-regs.h>
@@ -31,10 +32,29 @@ struct sm501_device {
struct platform_device pdev;
};

+struct sm501_gpio;
+
+struct sm501_gpio_chip {
+ struct gpio_chip gpio;
+ struct sm501_gpio *ourgpio; /* to get back to parent. */
+ void __iomem *regbase;
+};
+
+struct sm501_gpio {
+ struct sm501_gpio_chip low;
+ struct sm501_gpio_chip high;
+ spinlock_t lock;
+
+ unsigned int registered : 1;
+ void __iomem *regs;
+ struct resource *regs_res;
+};
+
struct sm501_devdata {
spinlock_t reg_lock;
struct mutex clock_lock;
struct list_head devices;
+ struct sm501_gpio gpio;

struct device *dev;
struct resource *io_res;
@@ -42,6 +62,7 @@ struct sm501_devdata {
struct resource *regs_claim;
struct sm501_platdata *platdata;

+
unsigned int in_suspend;
unsigned long pm_misc;

@@ -52,6 +73,7 @@ struct sm501_devdata {
unsigned int rev;
};

+
#define MHZ (1000 * 1000)

#ifdef DEBUG
@@ -276,58 +298,6 @@ unsigned long sm501_modify_reg(struct de

EXPORT_SYMBOL_GPL(sm501_modify_reg);

-unsigned long sm501_gpio_get(struct device *dev,
- unsigned long gpio)
-{
- struct sm501_devdata *sm = dev_get_drvdata(dev);
- unsigned long result;
- unsigned long reg;
-
- reg = (gpio > 32) ? SM501_GPIO_DATA_HIGH : SM501_GPIO_DATA_LOW;
- result = readl(sm->regs + reg);
-
- result >>= (gpio & 31);
- return result & 1UL;
-}
-
-EXPORT_SYMBOL_GPL(sm501_gpio_get);
-
-void sm501_gpio_set(struct device *dev,
- unsigned long gpio,
- unsigned int to,
- unsigned int dir)
-{
- struct sm501_devdata *sm = dev_get_drvdata(dev);
-
- unsigned long bit = 1 << (gpio & 31);
- unsigned long base;
- unsigned long save;
- unsigned long val;
-
- base = (gpio > 32) ? SM501_GPIO_DATA_HIGH : SM501_GPIO_DATA_LOW;
- base += SM501_GPIO;
-
- spin_lock_irqsave(&sm->reg_lock, save);
-
- val = readl(sm->regs + base) & ~bit;
- if (to)
- val |= bit;
- writel(val, sm->regs + base);
-
- val = readl(sm->regs + SM501_GPIO_DDR_LOW) & ~bit;
- if (dir)
- val |= bit;
-
- writel(val, sm->regs + SM501_GPIO_DDR_LOW);
- sm501_sync_regs(sm);
-
- spin_unlock_irqrestore(&sm->reg_lock, save);
-
-}
-
-EXPORT_SYMBOL_GPL(sm501_gpio_set);
-
-
/* sm501_unit_power
*
* alters the power active gate to set specific units on or off
@@ -906,6 +876,226 @@ static int sm501_register_display(struct
return sm501_register_device(sm, pdev);
}

+#ifdef CONFIG_MFD_SM501_GPIO
+
+static inline struct sm501_gpio_chip *to_sm501_gpio(struct gpio_chip *gc)
+{
+ return container_of(gc, struct sm501_gpio_chip, gpio);
+}
+
+static inline struct sm501_devdata *sm501_gpio_to_dev(struct sm501_gpio *gpio)
+{
+ return container_of(gpio, struct sm501_devdata, gpio);
+}
+
+static int sm501_gpio_get(struct gpio_chip *chip, unsigned offset)
+
+{
+ struct sm501_gpio_chip *smgpio = to_sm501_gpio(chip);
+ unsigned long result;
+
+ result = readl(smgpio->regbase + SM501_GPIO_DATA_LOW);
+ result >>= offset;
+
+ return result & 1UL;
+}
+
+static void sm501_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
+
+{
+ struct sm501_gpio_chip *smchip = to_sm501_gpio(chip);
+ struct sm501_gpio *smgpio = smchip->ourgpio;
+ unsigned long bit = 1 << offset;
+ void __iomem *regs = smchip->regbase;
+ unsigned long save;
+ unsigned long val;
+
+ dev_dbg(sm501_gpio_to_dev(smgpio)->dev, "%s(%p,%d)\n",
+ __func__, chip, offset);
+
+ spin_lock_irqsave(&smgpio->lock, save);
+
+ val = readl(regs + SM501_GPIO_DATA_LOW) & ~bit;
+ if (value)
+ val |= bit;
+ writel(val, regs);
+
+ sm501_sync_regs(sm501_gpio_to_dev(smgpio));
+ spin_unlock_irqrestore(&smgpio->lock, save);
+}
+
+static int sm501_gpio_input(struct gpio_chip *chip, unsigned offset)
+{
+ struct sm501_gpio_chip *smchip = to_sm501_gpio(chip);
+ struct sm501_gpio *smgpio = smchip->ourgpio;
+ void __iomem *regs = smchip->regbase;
+ unsigned long bit = 1 << offset;
+ unsigned long save;
+ unsigned long ddr;
+
+ dev_info(sm501_gpio_to_dev(smgpio)->dev, "%s(%p,%d)\n",
+ __func__, chip, offset);
+
+ spin_lock_irqsave(&smgpio->lock, save);
+
+ ddr = readl(regs + SM501_GPIO_DDR_LOW);
+ writel(ddr & ~bit, regs + SM501_GPIO_DDR_LOW);
+
+ sm501_sync_regs(sm501_gpio_to_dev(smgpio));
+ spin_unlock_irqrestore(&smgpio->lock, save);
+
+ return 0;
+}
+
+static int sm501_gpio_output(struct gpio_chip *chip,
+ unsigned offset, int value)
+{
+ struct sm501_gpio_chip *smchip = to_sm501_gpio(chip);
+ struct sm501_gpio *smgpio = smchip->ourgpio;
+ unsigned long bit = 1 << offset;
+ void __iomem *regs = smchip->regbase;
+ unsigned long save;
+ unsigned long val;
+ unsigned long ddr;
+
+ dev_dbg(sm501_gpio_to_dev(smgpio)->dev, "%s(%p,%d,%d)\n",
+ __func__, chip, offset, value);
+
+ spin_lock_irqsave(&smgpio->lock, save);
+
+ val = readl(regs + SM501_GPIO_DATA_LOW);
+ if (value)
+ val |= bit;
+ else
+ val &= ~bit;
+ writel(val, regs);
+
+ ddr = readl(regs + SM501_GPIO_DDR_LOW);
+ writel(ddr | bit, regs + SM501_GPIO_DDR_LOW);
+
+ sm501_sync_regs(sm501_gpio_to_dev(smgpio));
+ writel(val, regs + SM501_GPIO_DATA_LOW);
+
+ sm501_sync_regs(sm501_gpio_to_dev(smgpio));
+ spin_unlock_irqrestore(&smgpio->lock, save);
+
+ return 0;
+}
+
+static struct gpio_chip gpio_chip_template = {
+ .ngpio = 32,
+ .direction_input = sm501_gpio_input,
+ .direction_output = sm501_gpio_output,
+ .set = sm501_gpio_set,
+ .get = sm501_gpio_get,
+};
+
+static int __devinit sm501_gpio_register_chip(struct sm501_devdata *sm,
+ struct sm501_gpio *gpio,
+ struct sm501_gpio_chip *chip)
+{
+ struct sm501_platdata *pdata = sm->platdata;
+ struct gpio_chip *gchip = &chip->gpio;
+ unsigned base = pdata->gpio_base;
+
+ memcpy(chip, &gpio_chip_template, sizeof(struct gpio_chip));
+
+ if (chip == &gpio->high) {
+ base += 32;
+ chip->regbase = gpio->regs + SM501_GPIO_DATA_HIGH;
+ gchip->label = "SM501-HIGH";
+ } else {
+ chip->regbase = gpio->regs + SM501_GPIO_DATA_LOW;
+ gchip->label = "SM501-LOW";
+ }
+
+ gchip->base = base;
+ chip->ourgpio = gpio;
+
+ return gpiochip_add(gchip);
+}
+
+static int sm501_register_gpio(struct sm501_devdata *sm)
+{
+ struct sm501_gpio *gpio = &sm->gpio;
+ resource_size_t iobase = sm->io_res->start + SM501_GPIO;
+ int ret;
+ int tmp;
+
+ dev_dbg(sm->dev, "registering gpio block %08llx\n",
+ (unsigned long long)iobase);
+
+ spin_lock_init(&gpio->lock);
+
+ gpio->regs_res = request_mem_region(iobase, 0x20, "sm501-gpio");
+ if (gpio->regs_res == NULL) {
+ dev_err(sm->dev, "gpio: failed to request region\n");
+ return -ENXIO;
+ }
+
+ gpio->regs = ioremap(iobase, 0x20);
+ if (gpio->regs == NULL) {
+ dev_err(sm->dev, "gpio: failed to remap registers\n");
+ ret = -ENXIO;
+ goto err_mapped;
+ }
+
+ /* Register both our chips. */
+
+ ret = sm501_gpio_register_chip(sm, gpio, &gpio->low);
+ if (ret) {
+ dev_err(sm->dev, "failed to add low chip\n");
+ goto err_mapped;
+ }
+
+ ret = sm501_gpio_register_chip(sm, gpio, &gpio->high);
+ if (ret) {
+ dev_err(sm->dev, "failed to add high chip\n");
+ goto err_low_chip;
+ }
+
+ gpio->registered = 1;
+
+ return 0;
+
+ err_low_chip:
+ tmp = gpiochip_remove(&gpio->low.gpio);
+ if (tmp) {
+ dev_err(sm->dev, "cannot remove low chip, cannot tidy up\n");
+ return ret;
+ }
+
+ err_mapped:
+ release_resource(gpio->regs_res);
+ kfree(gpio->regs_res);
+
+ return ret;
+}
+
+static void sm501_gpio_remove(struct sm501_devdata *sm)
+{
+ int ret;
+
+ ret = gpiochip_remove(&sm->gpio.low.gpio);
+ if (ret)
+ dev_err(sm->dev, "cannot remove low chip, cannot tidy up\n");
+
+ ret = gpiochip_remove(&sm->gpio.high.gpio);
+ if (ret)
+ dev_err(sm->dev, "cannot remove high chip, cannot tidy up\n");
+}
+
+#else
+static int sm501_register_gpio(struct sm501_devdata *sm)
+{
+ return 0;
+}
+
+static void sm501_gpio_remove(struct sm501_devdata *sm)
+{
+}
+#endif
+
/* sm501_dbg_regs
*
* Debug attribute to attach to parent device to show core registers
@@ -1059,6 +1249,8 @@ static int sm501_init_dev(struct sm501_d
sm501_register_usbhost(sm, &mem_avail);
if (idata->devices & (SM501_USE_UART0 | SM501_USE_UART1))
sm501_register_uart(sm, idata->devices);
+ if (idata->devices & SM501_USE_GPIO)
+ sm501_register_gpio(sm);
}

ret = sm501_check_clocks(sm);
@@ -1366,6 +1558,9 @@ static void sm501_dev_remove(struct sm50
sm501_remove_sub(sm, smdev);

device_remove_file(sm->dev, &dev_attr_dbg_regs);
+
+ if (sm->gpio.registered)
+ sm501_gpio_remove(sm);
}

static void sm501_pci_remove(struct pci_dev *dev)
Index: linux-2.6.26-rc5-quilt1/drivers/mfd/Kconfig
===================================================================
--- linux-2.6.26-rc5-quilt1.orig/drivers/mfd/Kconfig 2008-06-11 11:29:37.000000000 +0100
+++ linux-2.6.26-rc5-quilt1/drivers/mfd/Kconfig 2008-06-11 11:31:57.000000000 +0100
@@ -15,6 +15,14 @@ config MFD_SM501
interface. The device may be connected by PCI or local bus with
varying functions enabled.

+config MFD_SM501_GPIO
+ bool "Export GPIO via GPIO layer"
+ depends on MFD_SM501 && HAVE_GPIO_LIB
+ ---help---
+ This option uses the gpio library layer to export the 64 GPIO
+ lines on the SM501. The platform data is used to supply the
+ base number for the first GPIO line to register.
+
config MFD_ASIC3
bool "Support for Compaq ASIC3"
depends on GENERIC_HARDIRQS && ARM

--
Ben (ben@xxxxxxxxx, http://www.fluff.org/)

'a smiley only costs 4 bytes'
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