--- /dev/null
+/*
+ * Intel ICH6-10, Series 5 and 6, Atom C2000 (Avoton/Rangeley) GPIO driver
+ *
+ * Copyright (C) 2010 Extreme Engineering Solutions.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/gpio.h>
+#include <linux/platform_device.h>
+#include <linux/mfd/lpc_ich.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 offset);
+ int (*get)(struct gpio_chip *chip, unsigned 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 platform_device *dev;
+ struct gpio_chip chip;
+ struct resource *gpio_base; /* GPIO IO base */
+ struct resource *pm_base; /* Power Mangagment 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 nr, int val, int verify)
+{
+ unsigned long flags;
+ u32 data, tmp;
+ int reg_nr = nr / 32;
+ int bit = nr & 0x1f;
+ int ret = 0;
+
+ 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 |= 1 << bit;
+ else
+ data &= ~(1 << 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);
+ if (verify && data != tmp)
+ ret = -EPERM;
+
+ spin_unlock_irqrestore(&ichx_priv.lock, flags);
+
+ return ret;
+}
+
+static int ichx_read_bit(int reg, unsigned 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 & (1 << bit) ? 1 : 0;
+}
+
+static bool ichx_gpio_check_available(struct gpio_chip *gpio, unsigned nr)
+{
+ return !!(ichx_priv.use_gpio & (1 << (nr / 32)));
+}
+
+static int ichx_gpio_get_direction(struct gpio_chip *gpio, unsigned nr)
+{
+ return ichx_read_bit(GPIO_IO_SEL, nr) ? GPIOF_DIR_IN : GPIOF_DIR_OUT;
+}
+
+static int ichx_gpio_direction_input(struct gpio_chip *gpio, unsigned nr)
+{
+ /*
+ * Try setting pin as an input and verify it worked since many pins
+ * are output-only.
+ */
+ if (ichx_write_bit(GPIO_IO_SEL, nr, 1, 1))
+ return -EINVAL;
+
+ return 0;
+}
+
+static int ichx_gpio_direction_output(struct gpio_chip *gpio, unsigned 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.
+ */
+ if (ichx_write_bit(GPIO_IO_SEL, nr, 0, 1))
+ return -EINVAL;
+
+ return 0;
+}
+
+static int ichx_gpio_get(struct gpio_chip *chip, unsigned nr)
+{
+ return ichx_read_bit(GPIO_LVL, nr);
+}
+
+static int ich6_gpio_get(struct gpio_chip *chip, unsigned 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(1 << (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) & (1 << nr) ? 1 : 0;
+ } else {
+ return ichx_gpio_get(chip, nr);
+ }
+}
+
+static int ichx_gpio_request(struct gpio_chip *chip, unsigned 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] & (1 << (nr & 0x1f)))
+ return 0;
+
+ return ichx_read_bit(GPIO_USE_SEL, nr) ? 0 : -ENODEV;
+}
+
+static int ich6_gpio_request(struct gpio_chip *chip, unsigned 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 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->dev = &ichx_priv.dev->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 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 & (1 << i)))
+ continue;
+ if (!request_region(
+ res_base->start + ichx_priv.desc->regs[0][i],
+ ichx_priv.desc->reglen[i], name))
+ goto request_err;
+ }
+ return 0;
+
+request_err:
+ /* Clean up: release already requested regions, if any */
+ for (i--; i >= 0; i--) {
+ if (!(use_gpio & (1 << i)))
+ continue;
+ release_region(res_base->start + ichx_priv.desc->regs[0][i],
+ ichx_priv.desc->reglen[i]);
+ }
+ return -EBUSY;
+}
+
+static void ichx_gpio_release_regions(struct resource *res_base, u8 use_gpio)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(ichx_priv.desc->regs[0]); i++) {
+ if (!(use_gpio & (1 << i)))
+ continue;
+ release_region(res_base->start + ichx_priv.desc->regs[0][i],
+ ichx_priv.desc->reglen[i]);
+ }
+}
+
+static int ichx_gpio_probe(struct platform_device *pdev)
+{
+ struct resource *res_base, *res_pm;
+ int err;
+ struct lpc_ich_info *ich_info = dev_get_platdata(&pdev->dev);
+
+ if (!ich_info)
+ return -ENODEV;
+
+ ichx_priv.dev = pdev;
+
+ 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;
+ }
+
+ spin_lock_init(&ichx_priv.lock);
+ res_base = platform_get_resource(pdev, IORESOURCE_IO, ICH_RES_GPIO);
+ ichx_priv.use_gpio = ich_info->use_gpio;
+ err = ichx_gpio_request_regions(res_base, pdev->name,
+ ichx_priv.use_gpio);
+ if (err)
+ return err;
+
+ ichx_priv.gpio_base = res_base;
+
+ /*
+ * If necessary, determine the I/O address of ACPI/power management
+ * registers which are needed to read the 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) {
+ pr_warn("ACPI BAR is unavailable, GPI 0 - 15 unavailable\n");
+ goto init;
+ }
+
+ if (!request_region(res_pm->start, resource_size(res_pm),
+ pdev->name)) {
+ pr_warn("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(&ichx_priv.chip);
+ if (err) {
+ pr_err("Failed to register GPIOs\n");
+ goto add_err;
+ }
+
+ pr_info("GPIO from %d to %d on %s\n", ichx_priv.chip.base,
+ ichx_priv.chip.base + ichx_priv.chip.ngpio - 1, DRV_NAME);
+
+ return 0;
+
+add_err:
+ ichx_gpio_release_regions(ichx_priv.gpio_base, ichx_priv.use_gpio);
+ if (ichx_priv.pm_base)
+ release_region(ichx_priv.pm_base->start,
+ resource_size(ichx_priv.pm_base));
+ return err;
+}
+
+static int ichx_gpio_remove(struct platform_device *pdev)
+{
+ gpiochip_remove(&ichx_priv.chip);
+
+ ichx_gpio_release_regions(ichx_priv.gpio_base, ichx_priv.use_gpio);
+ if (ichx_priv.pm_base)
+ release_region(ichx_priv.pm_base->start,
+ resource_size(ichx_priv.pm_base));
+
+ 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);
Code Review / kvmfornfv.git / blobdiff