// 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);