--- /dev/null
+/*
+ * 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;
+};
+
+/*----------------------------------------------------------------------*/
+
+static inline struct gpio_twl4030_priv *to_gpio_twl4030(struct gpio_chip *chip)
+{
+ return container_of(chip, struct gpio_twl4030_priv, gpio_chip);
+}
+
+/*
+ * 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 = to_gpio_twl4030(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->dev);
+ 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 = to_gpio_twl4030(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 = to_gpio_twl4030(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 = to_gpio_twl4030(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) ? 0 : 1;
+out:
+ mutex_unlock(&priv->mutex);
+ return ret;
+}
+
+static void twl_set(struct gpio_chip *chip, unsigned offset, int value)
+{
+ struct gpio_twl4030_priv *priv = to_gpio_twl4030(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 = to_gpio_twl4030(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 = to_gpio_twl4030(chip);
+
+ return (priv->irq_base && (offset < TWL4030_GPIO_MAX))
+ ? (priv->irq_base + offset)
+ : -EINVAL;
+}
+
+static 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 = irq_alloc_descs(-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.dev = &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(&priv->gpio_chip);
+ 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");
Code Review / kvmfornfv.git / blobdiff