1 files changed, 494 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-ich.c b/drivers/gpio/gpio-ich.c
new file mode 100644
index 000000000..de56c013a
--- /dev/null
+++ b/drivers/gpio/gpio-ich.c
@@ -0,0 +1,494 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Intel ICH6-10, Series 5 and 6, Atom C2000 (Avoton/Rangeley) GPIO driver
+ *
+ * Copyright (C) 2010 Extreme Engineering Solutions.
+ */
+
+
+#include <linux/bitops.h>
+#include <linux/gpio/driver.h>
+#include <linux/ioport.h>
+#include <linux/mfd/lpc_ich.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+
+#define DRV_NAME "gpio_ich"
+
+/*
+ * GPIO register offsets in GPIO I/O space.
+ * Each chunk of 32 GPIOs is manipulated via its own USE_SELx, IO_SELx, and
+ * LVLx registers.  Logic in the read/write functions takes a register and
+ * an absolute bit number and determines the proper register offset and bit
+ * number in that register.  For example, to read the value of GPIO bit 50
+ * the code would access offset ichx_regs[2(=GPIO_LVL)][1(=50/32)],
+ * bit 18 (50%32).
+ */
+enum GPIO_REG {
+	GPIO_USE_SEL = 0,
+	GPIO_IO_SEL,
+	GPIO_LVL,
+	GPO_BLINK
+};
+
+static const u8 ichx_regs[4][3] = {
+	{0x00, 0x30, 0x40},	/* USE_SEL[1-3] offsets */
+	{0x04, 0x34, 0x44},	/* IO_SEL[1-3] offsets */
+	{0x0c, 0x38, 0x48},	/* LVL[1-3] offsets */
+	{0x18, 0x18, 0x18},	/* BLINK offset */
+};
+
+static const u8 ichx_reglen[3] = {
+	0x30, 0x10, 0x10,
+};
+
+static const u8 avoton_regs[4][3] = {
+	{0x00, 0x80, 0x00},
+	{0x04, 0x84, 0x00},
+	{0x08, 0x88, 0x00},
+};
+
+static const u8 avoton_reglen[3] = {
+	0x10, 0x10, 0x00,
+};
+
+#define ICHX_WRITE(val, reg, base_res)	outl(val, (reg) + (base_res)->start)
+#define ICHX_READ(reg, base_res)	inl((reg) + (base_res)->start)
+
+struct ichx_desc {
+	/* Max GPIO pins the chipset can have */
+	uint ngpio;
+
+	/* chipset registers */
+	const u8 (*regs)[3];
+	const u8 *reglen;
+
+	/* GPO_BLINK is available on this chipset */
+	bool have_blink;
+
+	/* Whether the chipset has GPIO in GPE0_STS in the PM IO region */
+	bool uses_gpe0;
+
+	/* USE_SEL is bogus on some chipsets, eg 3100 */
+	u32 use_sel_ignore[3];
+
+	/* Some chipsets have quirks, let these use their own request/get */
+	int (*request)(struct gpio_chip *chip, unsigned int offset);
+	int (*get)(struct gpio_chip *chip, unsigned int offset);
+
+	/*
+	 * Some chipsets don't let reading output values on GPIO_LVL register
+	 * this option allows driver caching written output values
+	 */
+	bool use_outlvl_cache;
+};
+
+static struct {
+	spinlock_t lock;
+	struct device *dev;
+	struct gpio_chip chip;
+	struct resource *gpio_base;	/* GPIO IO base */
+	struct resource *pm_base;	/* Power Management IO base */
+	struct ichx_desc *desc;	/* Pointer to chipset-specific description */
+	u32 orig_gpio_ctrl;	/* Orig CTRL value, used to restore on exit */
+	u8 use_gpio;		/* Which GPIO groups are usable */
+	int outlvl_cache[3];	/* cached output values */
+} ichx_priv;
+
+static int modparam_gpiobase = -1;	/* dynamic */
+module_param_named(gpiobase, modparam_gpiobase, int, 0444);
+MODULE_PARM_DESC(gpiobase, "The GPIO number base. -1 means dynamic, which is the default.");
+
+static int ichx_write_bit(int reg, unsigned int nr, int val, int verify)
+{
+	unsigned long flags;
+	u32 data, tmp;
+	int reg_nr = nr / 32;
+	int bit = nr & 0x1f;
+
+	spin_lock_irqsave(&ichx_priv.lock, flags);
+
+	if (reg == GPIO_LVL && ichx_priv.desc->use_outlvl_cache)
+		data = ichx_priv.outlvl_cache[reg_nr];
+	else
+		data = ICHX_READ(ichx_priv.desc->regs[reg][reg_nr],
+				 ichx_priv.gpio_base);
+
+	if (val)
+		data |= BIT(bit);
+	else
+		data &= ~BIT(bit);
+	ICHX_WRITE(data, ichx_priv.desc->regs[reg][reg_nr],
+			 ichx_priv.gpio_base);
+	if (reg == GPIO_LVL && ichx_priv.desc->use_outlvl_cache)
+		ichx_priv.outlvl_cache[reg_nr] = data;
+
+	tmp = ICHX_READ(ichx_priv.desc->regs[reg][reg_nr],
+			ichx_priv.gpio_base);
+
+	spin_unlock_irqrestore(&ichx_priv.lock, flags);
+
+	return (verify && data != tmp) ? -EPERM : 0;
+}
+
+static int ichx_read_bit(int reg, unsigned int nr)
+{
+	unsigned long flags;
+	u32 data;
+	int reg_nr = nr / 32;
+	int bit = nr & 0x1f;
+
+	spin_lock_irqsave(&ichx_priv.lock, flags);
+
+	data = ICHX_READ(ichx_priv.desc->regs[reg][reg_nr],
+			 ichx_priv.gpio_base);
+
+	if (reg == GPIO_LVL && ichx_priv.desc->use_outlvl_cache)
+		data = ichx_priv.outlvl_cache[reg_nr] | data;
+
+	spin_unlock_irqrestore(&ichx_priv.lock, flags);
+
+	return !!(data & BIT(bit));
+}
+
+static bool ichx_gpio_check_available(struct gpio_chip *gpio, unsigned int nr)
+{
+	return !!(ichx_priv.use_gpio & BIT(nr / 32));
+}
+
+static int ichx_gpio_get_direction(struct gpio_chip *gpio, unsigned int nr)
+{
+	if (ichx_read_bit(GPIO_IO_SEL, nr))
+		return GPIO_LINE_DIRECTION_IN;
+
+	return GPIO_LINE_DIRECTION_OUT;
+}
+
+static int ichx_gpio_direction_input(struct gpio_chip *gpio, unsigned int nr)
+{
+	/*
+	 * Try setting pin as an input and verify it worked since many pins
+	 * are output-only.
+	 */
+	return ichx_write_bit(GPIO_IO_SEL, nr, 1, 1);
+}
+
+static int ichx_gpio_direction_output(struct gpio_chip *gpio, unsigned int nr,
+					int val)
+{
+	/* Disable blink hardware which is available for GPIOs from 0 to 31. */
+	if (nr < 32 && ichx_priv.desc->have_blink)
+		ichx_write_bit(GPO_BLINK, nr, 0, 0);
+
+	/* Set GPIO output value. */
+	ichx_write_bit(GPIO_LVL, nr, val, 0);
+
+	/*
+	 * Try setting pin as an output and verify it worked since many pins
+	 * are input-only.
+	 */
+	return ichx_write_bit(GPIO_IO_SEL, nr, 0, 1);
+}
+
+static int ichx_gpio_get(struct gpio_chip *chip, unsigned int nr)
+{
+	return ichx_read_bit(GPIO_LVL, nr);
+}
+
+static int ich6_gpio_get(struct gpio_chip *chip, unsigned int nr)
+{
+	unsigned long flags;
+	u32 data;
+
+	/*
+	 * GPI 0 - 15 need to be read from the power management registers on
+	 * a ICH6/3100 bridge.
+	 */
+	if (nr < 16) {
+		if (!ichx_priv.pm_base)
+			return -ENXIO;
+
+		spin_lock_irqsave(&ichx_priv.lock, flags);
+
+		/* GPI 0 - 15 are latched, write 1 to clear*/
+		ICHX_WRITE(BIT(16 + nr), 0, ichx_priv.pm_base);
+		data = ICHX_READ(0, ichx_priv.pm_base);
+
+		spin_unlock_irqrestore(&ichx_priv.lock, flags);
+
+		return !!((data >> 16) & BIT(nr));
+	} else {
+		return ichx_gpio_get(chip, nr);
+	}
+}
+
+static int ichx_gpio_request(struct gpio_chip *chip, unsigned int nr)
+{
+	if (!ichx_gpio_check_available(chip, nr))
+		return -ENXIO;
+
+	/*
+	 * Note we assume the BIOS properly set a bridge's USE value.  Some
+	 * chips (eg Intel 3100) have bogus USE values though, so first see if
+	 * the chipset's USE value can be trusted for this specific bit.
+	 * If it can't be trusted, assume that the pin can be used as a GPIO.
+	 */
+	if (ichx_priv.desc->use_sel_ignore[nr / 32] & BIT(nr & 0x1f))
+		return 0;
+
+	return ichx_read_bit(GPIO_USE_SEL, nr) ? 0 : -ENODEV;
+}
+
+static int ich6_gpio_request(struct gpio_chip *chip, unsigned int nr)
+{
+	/*
+	 * Fixups for bits 16 and 17 are necessary on the Intel ICH6/3100
+	 * bridge as they are controlled by USE register bits 0 and 1.  See
+	 * "Table 704 GPIO_USE_SEL1 register" in the i3100 datasheet for
+	 * additional info.
+	 */
+	if (nr == 16 || nr == 17)
+		nr -= 16;
+
+	return ichx_gpio_request(chip, nr);
+}
+
+static void ichx_gpio_set(struct gpio_chip *chip, unsigned int nr, int val)
+{
+	ichx_write_bit(GPIO_LVL, nr, val, 0);
+}
+
+static void ichx_gpiolib_setup(struct gpio_chip *chip)
+{
+	chip->owner = THIS_MODULE;
+	chip->label = DRV_NAME;
+	chip->parent = ichx_priv.dev;
+
+	/* Allow chip-specific overrides of request()/get() */
+	chip->request = ichx_priv.desc->request ?
+		ichx_priv.desc->request : ichx_gpio_request;
+	chip->get = ichx_priv.desc->get ?
+		ichx_priv.desc->get : ichx_gpio_get;
+
+	chip->set = ichx_gpio_set;
+	chip->get_direction = ichx_gpio_get_direction;
+	chip->direction_input = ichx_gpio_direction_input;
+	chip->direction_output = ichx_gpio_direction_output;
+	chip->base = modparam_gpiobase;
+	chip->ngpio = ichx_priv.desc->ngpio;
+	chip->can_sleep = false;
+	chip->dbg_show = NULL;
+}
+
+/* ICH6-based, 631xesb-based */
+static struct ichx_desc ich6_desc = {
+	/* Bridges using the ICH6 controller need fixups for GPIO 0 - 17 */
+	.request = ich6_gpio_request,
+	.get = ich6_gpio_get,
+
+	/* GPIO 0-15 are read in the GPE0_STS PM register */
+	.uses_gpe0 = true,
+
+	.ngpio = 50,
+	.have_blink = true,
+	.regs = ichx_regs,
+	.reglen = ichx_reglen,
+};
+
+/* Intel 3100 */
+static struct ichx_desc i3100_desc = {
+	/*
+	 * Bits 16,17, 20 of USE_SEL and bit 16 of USE_SEL2 always read 0 on
+	 * the Intel 3100.  See "Table 712. GPIO Summary Table" of 3100
+	 * Datasheet for more info.
+	 */
+	.use_sel_ignore = {0x00130000, 0x00010000, 0x0},
+
+	/* The 3100 needs fixups for GPIO 0 - 17 */
+	.request = ich6_gpio_request,
+	.get = ich6_gpio_get,
+
+	/* GPIO 0-15 are read in the GPE0_STS PM register */
+	.uses_gpe0 = true,
+
+	.ngpio = 50,
+	.regs = ichx_regs,
+	.reglen = ichx_reglen,
+};
+
+/* ICH7 and ICH8-based */
+static struct ichx_desc ich7_desc = {
+	.ngpio = 50,
+	.have_blink = true,
+	.regs = ichx_regs,
+	.reglen = ichx_reglen,
+};
+
+/* ICH9-based */
+static struct ichx_desc ich9_desc = {
+	.ngpio = 61,
+	.have_blink = true,
+	.regs = ichx_regs,
+	.reglen = ichx_reglen,
+};
+
+/* ICH10-based - Consumer/corporate versions have different amount of GPIO */
+static struct ichx_desc ich10_cons_desc = {
+	.ngpio = 61,
+	.have_blink = true,
+	.regs = ichx_regs,
+	.reglen = ichx_reglen,
+};
+static struct ichx_desc ich10_corp_desc = {
+	.ngpio = 72,
+	.have_blink = true,
+	.regs = ichx_regs,
+	.reglen = ichx_reglen,
+};
+
+/* Intel 5 series, 6 series, 3400 series, and C200 series */
+static struct ichx_desc intel5_desc = {
+	.ngpio = 76,
+	.regs = ichx_regs,
+	.reglen = ichx_reglen,
+};
+
+/* Avoton */
+static struct ichx_desc avoton_desc = {
+	/* Avoton has only 59 GPIOs, but we assume the first set of register
+	 * (Core) has 32 instead of 31 to keep gpio-ich compliance
+	 */
+	.ngpio = 60,
+	.regs = avoton_regs,
+	.reglen = avoton_reglen,
+	.use_outlvl_cache = true,
+};
+
+static int ichx_gpio_request_regions(struct device *dev,
+	struct resource *res_base, const char *name, u8 use_gpio)
+{
+	int i;
+
+	if (!res_base || !res_base->start || !res_base->end)
+		return -ENODEV;
+
+	for (i = 0; i < ARRAY_SIZE(ichx_priv.desc->regs[0]); i++) {
+		if (!(use_gpio & BIT(i)))
+			continue;
+		if (!devm_request_region(dev,
+				res_base->start + ichx_priv.desc->regs[0][i],
+				ichx_priv.desc->reglen[i], name))
+			return -EBUSY;
+	}
+	return 0;
+}
+
+static int ichx_gpio_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct lpc_ich_info *ich_info = dev_get_platdata(dev);
+	struct resource *res_base, *res_pm;
+	int err;
+
+	if (!ich_info)
+		return -ENODEV;
+
+	switch (ich_info->gpio_version) {
+	case ICH_I3100_GPIO:
+		ichx_priv.desc = &i3100_desc;
+		break;
+	case ICH_V5_GPIO:
+		ichx_priv.desc = &intel5_desc;
+		break;
+	case ICH_V6_GPIO:
+		ichx_priv.desc = &ich6_desc;
+		break;
+	case ICH_V7_GPIO:
+		ichx_priv.desc = &ich7_desc;
+		break;
+	case ICH_V9_GPIO:
+		ichx_priv.desc = &ich9_desc;
+		break;
+	case ICH_V10CORP_GPIO:
+		ichx_priv.desc = &ich10_corp_desc;
+		break;
+	case ICH_V10CONS_GPIO:
+		ichx_priv.desc = &ich10_cons_desc;
+		break;
+	case AVOTON_GPIO:
+		ichx_priv.desc = &avoton_desc;
+		break;
+	default:
+		return -ENODEV;
+	}
+
+	ichx_priv.dev = dev;
+	spin_lock_init(&ichx_priv.lock);
+
+	res_base = platform_get_resource(pdev, IORESOURCE_IO, ICH_RES_GPIO);
+	err = ichx_gpio_request_regions(dev, res_base, pdev->name,
+					ich_info->use_gpio);
+	if (err)
+		return err;
+
+	ichx_priv.gpio_base = res_base;
+	ichx_priv.use_gpio = ich_info->use_gpio;
+
+	/*
+	 * If necessary, determine the I/O address of ACPI/power management
+	 * registers which are needed to read the GPE0 register for GPI pins
+	 * 0 - 15 on some chipsets.
+	 */
+	if (!ichx_priv.desc->uses_gpe0)
+		goto init;
+
+	res_pm = platform_get_resource(pdev, IORESOURCE_IO, ICH_RES_GPE0);
+	if (!res_pm) {
+		dev_warn(dev, "ACPI BAR is unavailable, GPI 0 - 15 unavailable\n");
+		goto init;
+	}
+
+	if (!devm_request_region(dev, res_pm->start, resource_size(res_pm),
+				 pdev->name)) {
+		dev_warn(dev, "ACPI BAR is busy, GPI 0 - 15 unavailable\n");
+		goto init;
+	}
+
+	ichx_priv.pm_base = res_pm;
+
+init:
+	ichx_gpiolib_setup(&ichx_priv.chip);
+	err = gpiochip_add_data(&ichx_priv.chip, NULL);
+	if (err) {
+		dev_err(dev, "Failed to register GPIOs\n");
+		return err;
+	}
+
+	dev_info(dev, "GPIO from %d to %d\n", ichx_priv.chip.base,
+		 ichx_priv.chip.base + ichx_priv.chip.ngpio - 1);
+
+	return 0;
+}
+
+static int ichx_gpio_remove(struct platform_device *pdev)
+{
+	gpiochip_remove(&ichx_priv.chip);
+
+	return 0;
+}
+
+static struct platform_driver ichx_gpio_driver = {
+	.driver		= {
+		.name	= DRV_NAME,
+	},
+	.probe		= ichx_gpio_probe,
+	.remove		= ichx_gpio_remove,
+};
+
+module_platform_driver(ichx_gpio_driver);
+
+MODULE_AUTHOR("Peter Tyser <ptyser@xes-inc.com>");
+MODULE_DESCRIPTION("GPIO interface for Intel ICH series");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:"DRV_NAME);