/* * Access to GPIOs on TWL4030/TPS659x0 chips * * Copyright (C) 2006-2007 Texas Instruments, Inc. * Copyright (C) 2006 MontaVista Software, Inc. * * Code re-arranged and cleaned up by: * Syed Mohammed Khasim <x0khasim@ti.com> * * Initial Code: * Andy Lowe / Nishanth Menon * * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #include <linux/module.h> #include <linux/init.h> #include <linux/interrupt.h> #include <linux/kthread.h> #include <linux/irq.h> #include <linux/gpio.h> #include <linux/platform_device.h> #include <linux/of.h> #include <linux/irqdomain.h> #include <linux/i2c/twl.h> /* * The GPIO "subchip" supports 18 GPIOs which can be configured as * inputs or outputs, with pullups or pulldowns on each pin. Each * GPIO can trigger interrupts on either or both edges. * * GPIO interrupts can be fed to either of two IRQ lines; this is * intended to support multiple hosts. * * There are also two LED pins used sometimes as output-only GPIOs. */ /* genirq interfaces are not available to modules */ #ifdef MODULE #define is_module() true #else #define is_module() false #endif /* GPIO_CTRL Fields */ #define MASK_GPIO_CTRL_GPIO0CD1 BIT(0) #define MASK_GPIO_CTRL_GPIO1CD2 BIT(1) #define MASK_GPIO_CTRL_GPIO_ON BIT(2) /* Mask for GPIO registers when aggregated into a 32-bit integer */ #define GPIO_32_MASK 0x0003ffff struct gpio_twl4030_priv { struct gpio_chip gpio_chip; struct mutex mutex; int irq_base; /* Bitfields for state caching */ unsigned int usage_count; unsigned int direction; unsigned int out_state; }; /*----------------------------------------------------------------------*/ /* * To configure TWL4030 GPIO module registers */ static inline int gpio_twl4030_write(u8 address, u8 data) { return twl_i2c_write_u8(TWL4030_MODULE_GPIO, data, address); } /*----------------------------------------------------------------------*/ /* * LED register offsets from TWL_MODULE_LED base * PWMs A and B are dedicated to LEDs A and B, respectively. */ #define TWL4030_LED_LEDEN_REG 0x00 #define TWL4030_PWMAON_REG 0x01 #define TWL4030_PWMAOFF_REG 0x02 #define TWL4030_PWMBON_REG 0x03 #define TWL4030_PWMBOFF_REG 0x04 /* LEDEN bits */ #define LEDEN_LEDAON BIT(0) #define LEDEN_LEDBON BIT(1) #define LEDEN_LEDAEXT BIT(2) #define LEDEN_LEDBEXT BIT(3) #define LEDEN_LEDAPWM BIT(4) #define LEDEN_LEDBPWM BIT(5) #define LEDEN_PWM_LENGTHA BIT(6) #define LEDEN_PWM_LENGTHB BIT(7) #define PWMxON_LENGTH BIT(7) /*----------------------------------------------------------------------*/ /* * To read a TWL4030 GPIO module register */ static inline int gpio_twl4030_read(u8 address) { u8 data; int ret = 0; ret = twl_i2c_read_u8(TWL4030_MODULE_GPIO, &data, address); return (ret < 0) ? ret : data; } /*----------------------------------------------------------------------*/ static u8 cached_leden; /* The LED lines are open drain outputs ... a FET pulls to GND, so an * external pullup is needed. We could also expose the integrated PWM * as a LED brightness control; we initialize it as "always on". */ static void twl4030_led_set_value(int led, int value) { u8 mask = LEDEN_LEDAON | LEDEN_LEDAPWM; if (led) mask <<= 1; if (value) cached_leden &= ~mask; else cached_leden |= mask; WARN_ON_ONCE(twl_i2c_write_u8(TWL4030_MODULE_LED, cached_leden, TWL4030_LED_LEDEN_REG)); } static int twl4030_set_gpio_direction(int gpio, int is_input) { u8 d_bnk = gpio >> 3; u8 d_msk = BIT(gpio & 0x7); u8 reg = 0; u8 base = REG_GPIODATADIR1 + d_bnk; int ret = 0; ret = gpio_twl4030_read(base); if (ret >= 0) { if (is_input) reg = ret & ~d_msk; else reg = ret | d_msk; ret = gpio_twl4030_write(base, reg); } return ret; } static int twl4030_set_gpio_dataout(int gpio, int enable) { u8 d_bnk = gpio >> 3; u8 d_msk = BIT(gpio & 0x7); u8 base = 0; if (enable) base = REG_SETGPIODATAOUT1 + d_bnk; else base = REG_CLEARGPIODATAOUT1 + d_bnk; return gpio_twl4030_write(base, d_msk); } static int twl4030_get_gpio_datain(int gpio) { u8 d_bnk = gpio >> 3; u8 d_off = gpio & 0x7; u8 base = 0; int ret = 0; base = REG_GPIODATAIN1 + d_bnk; ret = gpio_twl4030_read(base); if (ret > 0) ret = (ret >> d_off) & 0x1; return ret; } /*----------------------------------------------------------------------*/ static int twl_request(struct gpio_chip *chip, unsigned offset) { struct gpio_twl4030_priv *priv = gpiochip_get_data(chip); int status = 0; mutex_lock(&priv->mutex); /* Support the two LED outputs as output-only GPIOs. */ if (offset >= TWL4030_GPIO_MAX) { u8 ledclr_mask = LEDEN_LEDAON | LEDEN_LEDAEXT | LEDEN_LEDAPWM | LEDEN_PWM_LENGTHA; u8 reg = TWL4030_PWMAON_REG; offset -= TWL4030_GPIO_MAX; if (offset) { ledclr_mask <<= 1; reg = TWL4030_PWMBON_REG; } /* initialize PWM to always-drive */ /* Configure PWM OFF register first */ status = twl_i2c_write_u8(TWL4030_MODULE_LED, 0x7f, reg + 1); if (status < 0) goto done; /* Followed by PWM ON register */ status = twl_i2c_write_u8(TWL4030_MODULE_LED, 0x7f, reg); if (status < 0) goto done; /* init LED to not-driven (high) */ status = twl_i2c_read_u8(TWL4030_MODULE_LED, &cached_leden, TWL4030_LED_LEDEN_REG); if (status < 0) goto done; cached_leden &= ~ledclr_mask; status = twl_i2c_write_u8(TWL4030_MODULE_LED, cached_leden, TWL4030_LED_LEDEN_REG); if (status < 0) goto done; status = 0; goto done; } /* on first use, turn GPIO module "on" */ if (!priv->usage_count) { struct twl4030_gpio_platform_data *pdata; u8 value = MASK_GPIO_CTRL_GPIO_ON; /* optionally have the first two GPIOs switch vMMC1 * and vMMC2 power supplies based on card presence. */ pdata = dev_get_platdata(chip->parent); if (pdata) value |= pdata->mmc_cd & 0x03; status = gpio_twl4030_write(REG_GPIO_CTRL, value); } done: if (!status) priv->usage_count |= BIT(offset); mutex_unlock(&priv->mutex); return status; } static void twl_free(struct gpio_chip *chip, unsigned offset) { struct gpio_twl4030_priv *priv = gpiochip_get_data(chip); mutex_lock(&priv->mutex); if (offset >= TWL4030_GPIO_MAX) { twl4030_led_set_value(offset - TWL4030_GPIO_MAX, 1); goto out; } priv->usage_count &= ~BIT(offset); /* on last use, switch off GPIO module */ if (!priv->usage_count) gpio_twl4030_write(REG_GPIO_CTRL, 0x0); out: mutex_unlock(&priv->mutex); } static int twl_direction_in(struct gpio_chip *chip, unsigned offset) { struct gpio_twl4030_priv *priv = gpiochip_get_data(chip); int ret; mutex_lock(&priv->mutex); if (offset < TWL4030_GPIO_MAX) ret = twl4030_set_gpio_direction(offset, 1); else ret = -EINVAL; /* LED outputs can't be set as input */ if (!ret) priv->direction &= ~BIT(offset); mutex_unlock(&priv->mutex); return ret; } static int twl_get(struct gpio_chip *chip, unsigned offset) { struct gpio_twl4030_priv *priv = gpiochip_get_data(chip); int ret; int status = 0; mutex_lock(&priv->mutex); if (!(priv->usage_count & BIT(offset))) { ret = -EPERM; goto out; } if (priv->direction & BIT(offset)) status = priv->out_state & BIT(offset); else status = twl4030_get_gpio_datain(offset); ret = (status < 0) ? status : !!status; out: mutex_unlock(&priv->mutex); return ret; } static void twl_set(struct gpio_chip *chip, unsigned offset, int value) { struct gpio_twl4030_priv *priv = gpiochip_get_data(chip); mutex_lock(&priv->mutex); if (offset < TWL4030_GPIO_MAX) twl4030_set_gpio_dataout(offset, value); else twl4030_led_set_value(offset - TWL4030_GPIO_MAX, value); if (value) priv->out_state |= BIT(offset); else priv->out_state &= ~BIT(offset); mutex_unlock(&priv->mutex); } static int twl_direction_out(struct gpio_chip *chip, unsigned offset, int value) { struct gpio_twl4030_priv *priv = gpiochip_get_data(chip); int ret = 0; mutex_lock(&priv->mutex); if (offset < TWL4030_GPIO_MAX) { ret = twl4030_set_gpio_direction(offset, 0); if (ret) { mutex_unlock(&priv->mutex); return ret; } } /* * LED gpios i.e. offset >= TWL4030_GPIO_MAX are always output */ priv->direction |= BIT(offset); mutex_unlock(&priv->mutex); twl_set(chip, offset, value); return ret; } static int twl_to_irq(struct gpio_chip *chip, unsigned offset) { struct gpio_twl4030_priv *priv = gpiochip_get_data(chip); return (priv->irq_base && (offset < TWL4030_GPIO_MAX)) ? (priv->irq_base + offset) : -EINVAL; } static const struct gpio_chip template_chip = { .label = "twl4030", .owner = THIS_MODULE, .request = twl_request, .free = twl_free, .direction_input = twl_direction_in, .get = twl_get, .direction_output = twl_direction_out, .set = twl_set, .to_irq = twl_to_irq, .can_sleep = true, }; /*----------------------------------------------------------------------*/ static int gpio_twl4030_pulls(u32 ups, u32 downs) { u8 message[5]; unsigned i, gpio_bit; /* For most pins, a pulldown was enabled by default. * We should have data that's specific to this board. */ for (gpio_bit = 1, i = 0; i < 5; i++) { u8 bit_mask; unsigned j; for (bit_mask = 0, j = 0; j < 8; j += 2, gpio_bit <<= 1) { if (ups & gpio_bit) bit_mask |= 1 << (j + 1); else if (downs & gpio_bit) bit_mask |= 1 << (j + 0); } message[i] = bit_mask; } return twl_i2c_write(TWL4030_MODULE_GPIO, message, REG_GPIOPUPDCTR1, 5); } static int gpio_twl4030_debounce(u32 debounce, u8 mmc_cd) { u8 message[3]; /* 30 msec of debouncing is always used for MMC card detect, * and is optional for everything else. */ message[0] = (debounce & 0xff) | (mmc_cd & 0x03); debounce >>= 8; message[1] = (debounce & 0xff); debounce >>= 8; message[2] = (debounce & 0x03); return twl_i2c_write(TWL4030_MODULE_GPIO, message, REG_GPIO_DEBEN1, 3); } static int gpio_twl4030_remove(struct platform_device *pdev); static struct twl4030_gpio_platform_data *of_gpio_twl4030(struct device *dev, struct twl4030_gpio_platform_data *pdata) { struct twl4030_gpio_platform_data *omap_twl_info; omap_twl_info = devm_kzalloc(dev, sizeof(*omap_twl_info), GFP_KERNEL); if (!omap_twl_info) return NULL; if (pdata) *omap_twl_info = *pdata; omap_twl_info->use_leds = of_property_read_bool(dev->of_node, "ti,use-leds"); of_property_read_u32(dev->of_node, "ti,debounce", &omap_twl_info->debounce); of_property_read_u32(dev->of_node, "ti,mmc-cd", (u32 *)&omap_twl_info->mmc_cd); of_property_read_u32(dev->of_node, "ti,pullups", &omap_twl_info->pullups); of_property_read_u32(dev->of_node, "ti,pulldowns", &omap_twl_info->pulldowns); return omap_twl_info; } static int gpio_twl4030_probe(struct platform_device *pdev) { struct twl4030_gpio_platform_data *pdata = dev_get_platdata(&pdev->dev); struct device_node *node = pdev->dev.of_node; struct gpio_twl4030_priv *priv; int ret, irq_base; priv = devm_kzalloc(&pdev->dev, sizeof(struct gpio_twl4030_priv), GFP_KERNEL); if (!priv) return -ENOMEM; /* maybe setup IRQs */ if (is_module()) { dev_err(&pdev->dev, "can't dispatch IRQs from modules\n"); goto no_irqs; } irq_base = devm_irq_alloc_descs(&pdev->dev, -1, 0, TWL4030_GPIO_MAX, 0); if (irq_base < 0) { dev_err(&pdev->dev, "Failed to alloc irq_descs\n"); return irq_base; } irq_domain_add_legacy(node, TWL4030_GPIO_MAX, irq_base, 0, &irq_domain_simple_ops, NULL); ret = twl4030_sih_setup(&pdev->dev, TWL4030_MODULE_GPIO, irq_base); if (ret < 0) return ret; priv->irq_base = irq_base; no_irqs: priv->gpio_chip = template_chip; priv->gpio_chip.base = -1; priv->gpio_chip.ngpio = TWL4030_GPIO_MAX; priv->gpio_chip.parent = &pdev->dev; mutex_init(&priv->mutex); if (node) pdata = of_gpio_twl4030(&pdev->dev, pdata); if (pdata == NULL) { dev_err(&pdev->dev, "Platform data is missing\n"); return -ENXIO; } /* * NOTE: boards may waste power if they don't set pullups * and pulldowns correctly ... default for non-ULPI pins is * pulldown, and some other pins may have external pullups * or pulldowns. Careful! */ ret = gpio_twl4030_pulls(pdata->pullups, pdata->pulldowns); if (ret) dev_dbg(&pdev->dev, "pullups %.05x %.05x --> %d\n", pdata->pullups, pdata->pulldowns, ret); ret = gpio_twl4030_debounce(pdata->debounce, pdata->mmc_cd); if (ret) dev_dbg(&pdev->dev, "debounce %.03x %.01x --> %d\n", pdata->debounce, pdata->mmc_cd, ret); /* * NOTE: we assume VIBRA_CTL.VIBRA_EN, in MODULE_AUDIO_VOICE, * is (still) clear if use_leds is set. */ if (pdata->use_leds) priv->gpio_chip.ngpio += 2; ret = gpiochip_add_data(&priv->gpio_chip, priv); if (ret < 0) { dev_err(&pdev->dev, "could not register gpiochip, %d\n", ret); priv->gpio_chip.ngpio = 0; gpio_twl4030_remove(pdev); goto out; } platform_set_drvdata(pdev, priv); if (pdata->setup) { int status; status = pdata->setup(&pdev->dev, priv->gpio_chip.base, TWL4030_GPIO_MAX); if (status) dev_dbg(&pdev->dev, "setup --> %d\n", status); } out: return ret; } /* Cannot use as gpio_twl4030_probe() calls us */ static int gpio_twl4030_remove(struct platform_device *pdev) { struct twl4030_gpio_platform_data *pdata = dev_get_platdata(&pdev->dev); struct gpio_twl4030_priv *priv = platform_get_drvdata(pdev); int status; if (pdata && pdata->teardown) { status = pdata->teardown(&pdev->dev, priv->gpio_chip.base, TWL4030_GPIO_MAX); if (status) { dev_dbg(&pdev->dev, "teardown --> %d\n", status); return status; } } gpiochip_remove(&priv->gpio_chip); if (is_module()) return 0; /* REVISIT no support yet for deregistering all the IRQs */ WARN_ON(1); return -EIO; } static const struct of_device_id twl_gpio_match[] = { { .compatible = "ti,twl4030-gpio", }, { }, }; MODULE_DEVICE_TABLE(of, twl_gpio_match); /* Note: this hardware lives inside an I2C-based multi-function device. */ MODULE_ALIAS("platform:twl4030_gpio"); static struct platform_driver gpio_twl4030_driver = { .driver = { .name = "twl4030_gpio", .of_match_table = twl_gpio_match, }, .probe = gpio_twl4030_probe, .remove = gpio_twl4030_remove, }; static int __init gpio_twl4030_init(void) { return platform_driver_register(&gpio_twl4030_driver); } subsys_initcall(gpio_twl4030_init); static void __exit gpio_twl4030_exit(void) { platform_driver_unregister(&gpio_twl4030_driver); } module_exit(gpio_twl4030_exit); MODULE_AUTHOR("Texas Instruments, Inc."); MODULE_DESCRIPTION("GPIO interface for TWL4030"); MODULE_LICENSE("GPL");