| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * AMD CS5535/CS5536 GPIO driver |
| * Copyright (C) 2006 Advanced Micro Devices, Inc. |
| * Copyright (C) 2007-2009 Andres Salomon <dilinger@collabora.co.uk> |
| */ |
| |
| #include <linux/kernel.h> |
| #include <linux/spinlock.h> |
| #include <linux/module.h> |
| #include <linux/platform_device.h> |
| #include <linux/gpio/driver.h> |
| #include <linux/io.h> |
| #include <linux/cs5535.h> |
| #include <asm/msr.h> |
| |
| #define DRV_NAME "cs5535-gpio" |
| |
| /* |
| * Some GPIO pins |
| * 31-29,23 : reserved (always mask out) |
| * 28 : Power Button |
| * 26 : PME# |
| * 22-16 : LPC |
| * 14,15 : SMBus |
| * 9,8 : UART1 |
| * 7 : PCI INTB |
| * 3,4 : UART2/DDC |
| * 2 : IDE_IRQ0 |
| * 1 : AC_BEEP |
| * 0 : PCI INTA |
| * |
| * If a mask was not specified, allow all except |
| * reserved and Power Button |
| */ |
| #define GPIO_DEFAULT_MASK 0x0F7FFFFF |
| |
| static ulong mask = GPIO_DEFAULT_MASK; |
| module_param_named(mask, mask, ulong, 0444); |
| MODULE_PARM_DESC(mask, "GPIO channel mask."); |
| |
| /* |
| * FIXME: convert this singleton driver to use the state container |
| * design pattern, see Documentation/driver-api/driver-model/design-patterns.rst |
| */ |
| static struct cs5535_gpio_chip { |
| struct gpio_chip chip; |
| resource_size_t base; |
| |
| struct platform_device *pdev; |
| spinlock_t lock; |
| } cs5535_gpio_chip; |
| |
| /* |
| * The CS5535/CS5536 GPIOs support a number of extra features not defined |
| * by the gpio_chip API, so these are exported. For a full list of the |
| * registers, see include/linux/cs5535.h. |
| */ |
| |
| static void errata_outl(struct cs5535_gpio_chip *chip, u32 val, |
| unsigned int reg) |
| { |
| unsigned long addr = chip->base + 0x80 + reg; |
| |
| /* |
| * According to the CS5536 errata (#36), after suspend |
| * a write to the high bank GPIO register will clear all |
| * non-selected bits; the recommended workaround is a |
| * read-modify-write operation. |
| * |
| * Don't apply this errata to the edge status GPIOs, as writing |
| * to their lower bits will clear them. |
| */ |
| if (reg != GPIO_POSITIVE_EDGE_STS && reg != GPIO_NEGATIVE_EDGE_STS) { |
| if (val & 0xffff) |
| val |= (inl(addr) & 0xffff); /* ignore the high bits */ |
| else |
| val |= (inl(addr) ^ (val >> 16)); |
| } |
| outl(val, addr); |
| } |
| |
| static void __cs5535_gpio_set(struct cs5535_gpio_chip *chip, unsigned offset, |
| unsigned int reg) |
| { |
| if (offset < 16) |
| /* low bank register */ |
| outl(1 << offset, chip->base + reg); |
| else |
| /* high bank register */ |
| errata_outl(chip, 1 << (offset - 16), reg); |
| } |
| |
| void cs5535_gpio_set(unsigned offset, unsigned int reg) |
| { |
| struct cs5535_gpio_chip *chip = &cs5535_gpio_chip; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&chip->lock, flags); |
| __cs5535_gpio_set(chip, offset, reg); |
| spin_unlock_irqrestore(&chip->lock, flags); |
| } |
| EXPORT_SYMBOL_GPL(cs5535_gpio_set); |
| |
| static void __cs5535_gpio_clear(struct cs5535_gpio_chip *chip, unsigned offset, |
| unsigned int reg) |
| { |
| if (offset < 16) |
| /* low bank register */ |
| outl(1 << (offset + 16), chip->base + reg); |
| else |
| /* high bank register */ |
| errata_outl(chip, 1 << offset, reg); |
| } |
| |
| void cs5535_gpio_clear(unsigned offset, unsigned int reg) |
| { |
| struct cs5535_gpio_chip *chip = &cs5535_gpio_chip; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&chip->lock, flags); |
| __cs5535_gpio_clear(chip, offset, reg); |
| spin_unlock_irqrestore(&chip->lock, flags); |
| } |
| EXPORT_SYMBOL_GPL(cs5535_gpio_clear); |
| |
| int cs5535_gpio_isset(unsigned offset, unsigned int reg) |
| { |
| struct cs5535_gpio_chip *chip = &cs5535_gpio_chip; |
| unsigned long flags; |
| long val; |
| |
| spin_lock_irqsave(&chip->lock, flags); |
| if (offset < 16) |
| /* low bank register */ |
| val = inl(chip->base + reg); |
| else { |
| /* high bank register */ |
| val = inl(chip->base + 0x80 + reg); |
| offset -= 16; |
| } |
| spin_unlock_irqrestore(&chip->lock, flags); |
| |
| return (val & (1 << offset)) ? 1 : 0; |
| } |
| EXPORT_SYMBOL_GPL(cs5535_gpio_isset); |
| |
| int cs5535_gpio_set_irq(unsigned group, unsigned irq) |
| { |
| uint32_t lo, hi; |
| |
| if (group > 7 || irq > 15) |
| return -EINVAL; |
| |
| rdmsr(MSR_PIC_ZSEL_HIGH, lo, hi); |
| |
| lo &= ~(0xF << (group * 4)); |
| lo |= (irq & 0xF) << (group * 4); |
| |
| wrmsr(MSR_PIC_ZSEL_HIGH, lo, hi); |
| return 0; |
| } |
| EXPORT_SYMBOL_GPL(cs5535_gpio_set_irq); |
| |
| void cs5535_gpio_setup_event(unsigned offset, int pair, int pme) |
| { |
| struct cs5535_gpio_chip *chip = &cs5535_gpio_chip; |
| uint32_t shift = (offset % 8) * 4; |
| unsigned long flags; |
| uint32_t val; |
| |
| if (offset >= 24) |
| offset = GPIO_MAP_W; |
| else if (offset >= 16) |
| offset = GPIO_MAP_Z; |
| else if (offset >= 8) |
| offset = GPIO_MAP_Y; |
| else |
| offset = GPIO_MAP_X; |
| |
| spin_lock_irqsave(&chip->lock, flags); |
| val = inl(chip->base + offset); |
| |
| /* Clear whatever was there before */ |
| val &= ~(0xF << shift); |
| |
| /* Set the new value */ |
| val |= ((pair & 7) << shift); |
| |
| /* Set the PME bit if this is a PME event */ |
| if (pme) |
| val |= (1 << (shift + 3)); |
| |
| outl(val, chip->base + offset); |
| spin_unlock_irqrestore(&chip->lock, flags); |
| } |
| EXPORT_SYMBOL_GPL(cs5535_gpio_setup_event); |
| |
| /* |
| * Generic gpio_chip API support. |
| */ |
| |
| static int chip_gpio_request(struct gpio_chip *c, unsigned offset) |
| { |
| struct cs5535_gpio_chip *chip = gpiochip_get_data(c); |
| unsigned long flags; |
| |
| spin_lock_irqsave(&chip->lock, flags); |
| |
| /* check if this pin is available */ |
| if ((mask & (1 << offset)) == 0) { |
| dev_info(&chip->pdev->dev, |
| "pin %u is not available (check mask)\n", offset); |
| spin_unlock_irqrestore(&chip->lock, flags); |
| return -EINVAL; |
| } |
| |
| /* disable output aux 1 & 2 on this pin */ |
| __cs5535_gpio_clear(chip, offset, GPIO_OUTPUT_AUX1); |
| __cs5535_gpio_clear(chip, offset, GPIO_OUTPUT_AUX2); |
| |
| /* disable input aux 1 on this pin */ |
| __cs5535_gpio_clear(chip, offset, GPIO_INPUT_AUX1); |
| |
| spin_unlock_irqrestore(&chip->lock, flags); |
| |
| return 0; |
| } |
| |
| static int chip_gpio_get(struct gpio_chip *chip, unsigned offset) |
| { |
| return cs5535_gpio_isset(offset, GPIO_READ_BACK); |
| } |
| |
| static void chip_gpio_set(struct gpio_chip *chip, unsigned offset, int val) |
| { |
| if (val) |
| cs5535_gpio_set(offset, GPIO_OUTPUT_VAL); |
| else |
| cs5535_gpio_clear(offset, GPIO_OUTPUT_VAL); |
| } |
| |
| static int chip_direction_input(struct gpio_chip *c, unsigned offset) |
| { |
| struct cs5535_gpio_chip *chip = gpiochip_get_data(c); |
| unsigned long flags; |
| |
| spin_lock_irqsave(&chip->lock, flags); |
| __cs5535_gpio_set(chip, offset, GPIO_INPUT_ENABLE); |
| __cs5535_gpio_clear(chip, offset, GPIO_OUTPUT_ENABLE); |
| spin_unlock_irqrestore(&chip->lock, flags); |
| |
| return 0; |
| } |
| |
| static int chip_direction_output(struct gpio_chip *c, unsigned offset, int val) |
| { |
| struct cs5535_gpio_chip *chip = gpiochip_get_data(c); |
| unsigned long flags; |
| |
| spin_lock_irqsave(&chip->lock, flags); |
| |
| __cs5535_gpio_set(chip, offset, GPIO_INPUT_ENABLE); |
| __cs5535_gpio_set(chip, offset, GPIO_OUTPUT_ENABLE); |
| if (val) |
| __cs5535_gpio_set(chip, offset, GPIO_OUTPUT_VAL); |
| else |
| __cs5535_gpio_clear(chip, offset, GPIO_OUTPUT_VAL); |
| |
| spin_unlock_irqrestore(&chip->lock, flags); |
| |
| return 0; |
| } |
| |
| static const char * const cs5535_gpio_names[] = { |
| "GPIO0", "GPIO1", "GPIO2", "GPIO3", |
| "GPIO4", "GPIO5", "GPIO6", "GPIO7", |
| "GPIO8", "GPIO9", "GPIO10", "GPIO11", |
| "GPIO12", "GPIO13", "GPIO14", "GPIO15", |
| "GPIO16", "GPIO17", "GPIO18", "GPIO19", |
| "GPIO20", "GPIO21", "GPIO22", NULL, |
| "GPIO24", "GPIO25", "GPIO26", "GPIO27", |
| "GPIO28", NULL, NULL, NULL, |
| }; |
| |
| static struct cs5535_gpio_chip cs5535_gpio_chip = { |
| .chip = { |
| .owner = THIS_MODULE, |
| .label = DRV_NAME, |
| |
| .base = 0, |
| .ngpio = 32, |
| .names = cs5535_gpio_names, |
| .request = chip_gpio_request, |
| |
| .get = chip_gpio_get, |
| .set = chip_gpio_set, |
| |
| .direction_input = chip_direction_input, |
| .direction_output = chip_direction_output, |
| }, |
| }; |
| |
| static int cs5535_gpio_probe(struct platform_device *pdev) |
| { |
| struct resource *res; |
| int err = -EIO; |
| ulong mask_orig = mask; |
| |
| /* There are two ways to get the GPIO base address; one is by |
| * fetching it from MSR_LBAR_GPIO, the other is by reading the |
| * PCI BAR info. The latter method is easier (especially across |
| * different architectures), so we'll stick with that for now. If |
| * it turns out to be unreliable in the face of crappy BIOSes, we |
| * can always go back to using MSRs.. */ |
| |
| res = platform_get_resource(pdev, IORESOURCE_IO, 0); |
| if (!res) { |
| dev_err(&pdev->dev, "can't fetch device resource info\n"); |
| return err; |
| } |
| |
| if (!devm_request_region(&pdev->dev, res->start, resource_size(res), |
| pdev->name)) { |
| dev_err(&pdev->dev, "can't request region\n"); |
| return err; |
| } |
| |
| /* set up the driver-specific struct */ |
| cs5535_gpio_chip.base = res->start; |
| cs5535_gpio_chip.pdev = pdev; |
| spin_lock_init(&cs5535_gpio_chip.lock); |
| |
| dev_info(&pdev->dev, "reserved resource region %pR\n", res); |
| |
| /* mask out reserved pins */ |
| mask &= 0x1F7FFFFF; |
| |
| /* do not allow pin 28, Power Button, as there's special handling |
| * in the PMC needed. (note 12, p. 48) */ |
| mask &= ~(1 << 28); |
| |
| if (mask_orig != mask) |
| dev_info(&pdev->dev, "mask changed from 0x%08lX to 0x%08lX\n", |
| mask_orig, mask); |
| |
| /* finally, register with the generic GPIO API */ |
| err = devm_gpiochip_add_data(&pdev->dev, &cs5535_gpio_chip.chip, |
| &cs5535_gpio_chip); |
| if (err) |
| return err; |
| |
| return 0; |
| } |
| |
| static struct platform_driver cs5535_gpio_driver = { |
| .driver = { |
| .name = DRV_NAME, |
| }, |
| .probe = cs5535_gpio_probe, |
| }; |
| |
| module_platform_driver(cs5535_gpio_driver); |
| |
| MODULE_AUTHOR("Andres Salomon <dilinger@queued.net>"); |
| MODULE_DESCRIPTION("AMD CS5535/CS5536 GPIO driver"); |
| MODULE_LICENSE("GPL"); |
| MODULE_ALIAS("platform:" DRV_NAME); |