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-rw-r--r--drivers/gpio/sx150x.c645
1 files changed, 645 insertions, 0 deletions
diff --git a/drivers/gpio/sx150x.c b/drivers/gpio/sx150x.c
new file mode 100644
index 00000000000..b42f42ca70c
--- /dev/null
+++ b/drivers/gpio/sx150x.c
@@ -0,0 +1,645 @@
+/* Copyright (c) 2010, Code Aurora Forum. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * 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., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+#include <linux/gpio.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <linux/workqueue.h>
+#include <linux/i2c/sx150x.h>
+
+struct sx150x_device_data {
+ u8 reg_pullup;
+ u8 reg_pulldn;
+ u8 reg_drain;
+ u8 reg_polarity;
+ u8 reg_dir;
+ u8 reg_data;
+ u8 reg_irq_mask;
+ u8 reg_irq_src;
+ u8 reg_sense;
+ u8 reg_clock;
+ u8 reg_misc;
+ u8 reg_reset;
+ u8 ngpios;
+};
+
+struct sx150x_chip {
+ struct gpio_chip gpio_chip;
+ struct i2c_client *client;
+ const struct sx150x_device_data *dev_cfg;
+ int irq_summary;
+ int irq_base;
+ u32 irq_sense;
+ unsigned long irq_set_type_pending;
+ struct irq_chip irq_chip;
+ struct mutex lock;
+};
+
+static const struct sx150x_device_data sx150x_devices[] = {
+ [0] = { /* sx1508q */
+ .reg_pullup = 0x03,
+ .reg_pulldn = 0x04,
+ .reg_drain = 0x05,
+ .reg_polarity = 0x06,
+ .reg_dir = 0x07,
+ .reg_data = 0x08,
+ .reg_irq_mask = 0x09,
+ .reg_irq_src = 0x0c,
+ .reg_sense = 0x0b,
+ .reg_clock = 0x0f,
+ .reg_misc = 0x10,
+ .reg_reset = 0x7d,
+ .ngpios = 8
+ },
+ [1] = { /* sx1509q */
+ .reg_pullup = 0x07,
+ .reg_pulldn = 0x09,
+ .reg_drain = 0x0b,
+ .reg_polarity = 0x0d,
+ .reg_dir = 0x0f,
+ .reg_data = 0x11,
+ .reg_irq_mask = 0x13,
+ .reg_irq_src = 0x19,
+ .reg_sense = 0x17,
+ .reg_clock = 0x1e,
+ .reg_misc = 0x1f,
+ .reg_reset = 0x7d,
+ .ngpios = 16
+ },
+};
+
+static const struct i2c_device_id sx150x_id[] = {
+ {"sx1508q", 0},
+ {"sx1509q", 1},
+ {}
+};
+MODULE_DEVICE_TABLE(i2c, sx150x_id);
+
+static s32 sx150x_i2c_write(struct i2c_client *client, u8 reg, u8 val)
+{
+ s32 err = i2c_smbus_write_byte_data(client, reg, val);
+
+ if (err < 0)
+ dev_warn(&client->dev,
+ "i2c write fail: can't write %02x to %02x: %d\n",
+ val, reg, err);
+ return err;
+}
+
+static s32 sx150x_i2c_read(struct i2c_client *client, u8 reg, u8 *val)
+{
+ s32 err = i2c_smbus_read_byte_data(client, reg);
+
+ if (err >= 0)
+ *val = err;
+ else
+ dev_warn(&client->dev,
+ "i2c read fail: can't read from %02x: %d\n",
+ reg, err);
+ return err;
+}
+
+static inline bool offset_is_oscio(struct sx150x_chip *chip, unsigned offset)
+{
+ return (chip->dev_cfg->ngpios == offset);
+}
+
+/*
+ * These utility functions solve the common problem of locating and setting
+ * configuration bits. Configuration bits are grouped into registers
+ * whose indexes increase downwards. For example, with eight-bit registers,
+ * sixteen gpios would have their config bits grouped in the following order:
+ * REGISTER N-1 [ f e d c b a 9 8 ]
+ * N [ 7 6 5 4 3 2 1 0 ]
+ *
+ * For multi-bit configurations, the pattern gets wider:
+ * REGISTER N-3 [ f f e e d d c c ]
+ * N-2 [ b b a a 9 9 8 8 ]
+ * N-1 [ 7 7 6 6 5 5 4 4 ]
+ * N [ 3 3 2 2 1 1 0 0 ]
+ *
+ * Given the address of the starting register 'N', the index of the gpio
+ * whose configuration we seek to change, and the width in bits of that
+ * configuration, these functions allow us to locate the correct
+ * register and mask the correct bits.
+ */
+static inline void sx150x_find_cfg(u8 offset, u8 width,
+ u8 *reg, u8 *mask, u8 *shift)
+{
+ *reg -= offset * width / 8;
+ *mask = (1 << width) - 1;
+ *shift = (offset * width) % 8;
+ *mask <<= *shift;
+}
+
+static s32 sx150x_write_cfg(struct sx150x_chip *chip,
+ u8 offset, u8 width, u8 reg, u8 val)
+{
+ u8 mask;
+ u8 data;
+ u8 shift;
+ s32 err;
+
+ sx150x_find_cfg(offset, width, &reg, &mask, &shift);
+ err = sx150x_i2c_read(chip->client, reg, &data);
+ if (err < 0)
+ return err;
+
+ data &= ~mask;
+ data |= (val << shift) & mask;
+ return sx150x_i2c_write(chip->client, reg, data);
+}
+
+static int sx150x_get_io(struct sx150x_chip *chip, unsigned offset)
+{
+ u8 reg = chip->dev_cfg->reg_data;
+ u8 mask;
+ u8 data;
+ u8 shift;
+ s32 err;
+
+ sx150x_find_cfg(offset, 1, &reg, &mask, &shift);
+ err = sx150x_i2c_read(chip->client, reg, &data);
+ if (err >= 0)
+ err = (data & mask) != 0 ? 1 : 0;
+
+ return err;
+}
+
+static void sx150x_set_oscio(struct sx150x_chip *chip, int val)
+{
+ sx150x_i2c_write(chip->client,
+ chip->dev_cfg->reg_clock,
+ (val ? 0x1f : 0x10));
+}
+
+static void sx150x_set_io(struct sx150x_chip *chip, unsigned offset, int val)
+{
+ sx150x_write_cfg(chip,
+ offset,
+ 1,
+ chip->dev_cfg->reg_data,
+ (val ? 1 : 0));
+}
+
+static int sx150x_io_input(struct sx150x_chip *chip, unsigned offset)
+{
+ return sx150x_write_cfg(chip,
+ offset,
+ 1,
+ chip->dev_cfg->reg_dir,
+ 1);
+}
+
+static int sx150x_io_output(struct sx150x_chip *chip, unsigned offset, int val)
+{
+ int err;
+
+ err = sx150x_write_cfg(chip,
+ offset,
+ 1,
+ chip->dev_cfg->reg_data,
+ (val ? 1 : 0));
+ if (err >= 0)
+ err = sx150x_write_cfg(chip,
+ offset,
+ 1,
+ chip->dev_cfg->reg_dir,
+ 0);
+ return err;
+}
+
+static int sx150x_gpio_get(struct gpio_chip *gc, unsigned offset)
+{
+ struct sx150x_chip *chip;
+ int status = -EINVAL;
+
+ chip = container_of(gc, struct sx150x_chip, gpio_chip);
+
+ if (!offset_is_oscio(chip, offset)) {
+ mutex_lock(&chip->lock);
+ status = sx150x_get_io(chip, offset);
+ mutex_unlock(&chip->lock);
+ }
+
+ return status;
+}
+
+static void sx150x_gpio_set(struct gpio_chip *gc, unsigned offset, int val)
+{
+ struct sx150x_chip *chip;
+
+ chip = container_of(gc, struct sx150x_chip, gpio_chip);
+
+ mutex_lock(&chip->lock);
+ if (offset_is_oscio(chip, offset))
+ sx150x_set_oscio(chip, val);
+ else
+ sx150x_set_io(chip, offset, val);
+ mutex_unlock(&chip->lock);
+}
+
+static int sx150x_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
+{
+ struct sx150x_chip *chip;
+ int status = -EINVAL;
+
+ chip = container_of(gc, struct sx150x_chip, gpio_chip);
+
+ if (!offset_is_oscio(chip, offset)) {
+ mutex_lock(&chip->lock);
+ status = sx150x_io_input(chip, offset);
+ mutex_unlock(&chip->lock);
+ }
+ return status;
+}
+
+static int sx150x_gpio_direction_output(struct gpio_chip *gc,
+ unsigned offset,
+ int val)
+{
+ struct sx150x_chip *chip;
+ int status = 0;
+
+ chip = container_of(gc, struct sx150x_chip, gpio_chip);
+
+ if (!offset_is_oscio(chip, offset)) {
+ mutex_lock(&chip->lock);
+ status = sx150x_io_output(chip, offset, val);
+ mutex_unlock(&chip->lock);
+ }
+ return status;
+}
+
+static int sx150x_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
+{
+ struct sx150x_chip *chip;
+
+ chip = container_of(gc, struct sx150x_chip, gpio_chip);
+
+ if (offset >= chip->dev_cfg->ngpios)
+ return -EINVAL;
+
+ if (chip->irq_base < 0)
+ return -EINVAL;
+
+ return chip->irq_base + offset;
+}
+
+static void sx150x_irq_mask(unsigned int irq)
+{
+ struct irq_chip *ic = get_irq_chip(irq);
+ struct sx150x_chip *chip;
+ unsigned n;
+
+ chip = container_of(ic, struct sx150x_chip, irq_chip);
+ n = irq - chip->irq_base;
+
+ sx150x_write_cfg(chip, n, 1, chip->dev_cfg->reg_irq_mask, 1);
+ sx150x_write_cfg(chip, n, 2, chip->dev_cfg->reg_sense, 0);
+}
+
+static void sx150x_irq_unmask(unsigned int irq)
+{
+ struct irq_chip *ic = get_irq_chip(irq);
+ struct sx150x_chip *chip;
+ unsigned n;
+
+ chip = container_of(ic, struct sx150x_chip, irq_chip);
+ n = irq - chip->irq_base;
+
+ sx150x_write_cfg(chip, n, 1, chip->dev_cfg->reg_irq_mask, 0);
+ sx150x_write_cfg(chip, n, 2, chip->dev_cfg->reg_sense,
+ chip->irq_sense >> (n * 2));
+}
+
+static int sx150x_irq_set_type(unsigned int irq, unsigned int flow_type)
+{
+ struct irq_chip *ic = get_irq_chip(irq);
+ struct sx150x_chip *chip;
+ unsigned n, val = 0;
+
+ if (flow_type & (IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW))
+ return -EINVAL;
+
+ chip = container_of(ic, struct sx150x_chip, irq_chip);
+ n = irq - chip->irq_base;
+
+ if (flow_type & IRQ_TYPE_EDGE_RISING)
+ val |= 0x1;
+ if (flow_type & IRQ_TYPE_EDGE_FALLING)
+ val |= 0x2;
+
+ chip->irq_sense &= ~(3UL << (n * 2));
+ chip->irq_sense |= val << (n * 2);
+ chip->irq_set_type_pending |= BIT(n);
+ return 0;
+}
+
+static irqreturn_t sx150x_irq_thread_fn(int irq, void *dev_id)
+{
+ struct sx150x_chip *chip = (struct sx150x_chip *)dev_id;
+ unsigned nhandled = 0;
+ unsigned sub_irq;
+ unsigned n;
+ s32 err;
+ u8 val;
+ int i;
+
+ for (i = (chip->dev_cfg->ngpios / 8) - 1; i >= 0; --i) {
+ err = sx150x_i2c_read(chip->client,
+ chip->dev_cfg->reg_irq_src - i,
+ &val);
+ if (err < 0)
+ continue;
+
+ sx150x_i2c_write(chip->client,
+ chip->dev_cfg->reg_irq_src - i,
+ val);
+ for (n = 0; n < 8; ++n) {
+ if (val & (1 << n)) {
+ sub_irq = chip->irq_base + (i * 8) + n;
+ handle_nested_irq(sub_irq);
+ ++nhandled;
+ }
+ }
+ }
+
+ return (nhandled > 0 ? IRQ_HANDLED : IRQ_NONE);
+}
+
+static void sx150x_irq_bus_lock(unsigned int irq)
+{
+ struct irq_chip *ic = get_irq_chip(irq);
+ struct sx150x_chip *chip;
+
+ chip = container_of(ic, struct sx150x_chip, irq_chip);
+
+ mutex_lock(&chip->lock);
+}
+
+static void sx150x_irq_bus_sync_unlock(unsigned int irq)
+{
+ struct irq_chip *ic = get_irq_chip(irq);
+ struct sx150x_chip *chip;
+ unsigned n;
+
+ chip = container_of(ic, struct sx150x_chip, irq_chip);
+
+ while (chip->irq_set_type_pending) {
+ n = __ffs(chip->irq_set_type_pending);
+ chip->irq_set_type_pending &= ~BIT(n);
+ if (!(irq_to_desc(n + chip->irq_base)->status & IRQ_MASKED))
+ sx150x_write_cfg(chip, n, 2,
+ chip->dev_cfg->reg_sense,
+ chip->irq_sense >> (n * 2));
+ }
+
+ mutex_unlock(&chip->lock);
+}
+
+static void sx150x_init_chip(struct sx150x_chip *chip,
+ struct i2c_client *client,
+ kernel_ulong_t driver_data,
+ struct sx150x_platform_data *pdata)
+{
+ mutex_init(&chip->lock);
+
+ chip->client = client;
+ chip->dev_cfg = &sx150x_devices[driver_data];
+ chip->gpio_chip.label = client->name;
+ chip->gpio_chip.direction_input = sx150x_gpio_direction_input;
+ chip->gpio_chip.direction_output = sx150x_gpio_direction_output;
+ chip->gpio_chip.get = sx150x_gpio_get;
+ chip->gpio_chip.set = sx150x_gpio_set;
+ chip->gpio_chip.to_irq = sx150x_gpio_to_irq;
+ chip->gpio_chip.base = pdata->gpio_base;
+ chip->gpio_chip.can_sleep = 1;
+ chip->gpio_chip.ngpio = chip->dev_cfg->ngpios;
+ if (pdata->oscio_is_gpo)
+ ++chip->gpio_chip.ngpio;
+
+ chip->irq_chip.name = client->name;
+ chip->irq_chip.mask = sx150x_irq_mask;
+ chip->irq_chip.unmask = sx150x_irq_unmask;
+ chip->irq_chip.set_type = sx150x_irq_set_type;
+ chip->irq_chip.bus_lock = sx150x_irq_bus_lock;
+ chip->irq_chip.bus_sync_unlock = sx150x_irq_bus_sync_unlock;
+ chip->irq_summary = -1;
+ chip->irq_base = -1;
+ chip->irq_sense = 0;
+ chip->irq_set_type_pending = 0;
+}
+
+static int sx150x_init_io(struct sx150x_chip *chip, u8 base, u16 cfg)
+{
+ int err = 0;
+ unsigned n;
+
+ for (n = 0; err >= 0 && n < (chip->dev_cfg->ngpios / 8); ++n)
+ err = sx150x_i2c_write(chip->client, base - n, cfg >> (n * 8));
+ return err;
+}
+
+static int sx150x_init_hw(struct sx150x_chip *chip,
+ struct sx150x_platform_data *pdata)
+{
+ int err = 0;
+
+ err = i2c_smbus_write_word_data(chip->client,
+ chip->dev_cfg->reg_reset,
+ 0x3412);
+ if (err < 0)
+ return err;
+
+ err = sx150x_i2c_write(chip->client,
+ chip->dev_cfg->reg_misc,
+ 0x01);
+ if (err < 0)
+ return err;
+
+ err = sx150x_init_io(chip, chip->dev_cfg->reg_pullup,
+ pdata->io_pullup_ena);
+ if (err < 0)
+ return err;
+
+ err = sx150x_init_io(chip, chip->dev_cfg->reg_pulldn,
+ pdata->io_pulldn_ena);
+ if (err < 0)
+ return err;
+
+ err = sx150x_init_io(chip, chip->dev_cfg->reg_drain,
+ pdata->io_open_drain_ena);
+ if (err < 0)
+ return err;
+
+ err = sx150x_init_io(chip, chip->dev_cfg->reg_polarity,
+ pdata->io_polarity);
+ if (err < 0)
+ return err;
+
+ if (pdata->oscio_is_gpo)
+ sx150x_set_oscio(chip, 0);
+
+ return err;
+}
+
+static int sx150x_install_irq_chip(struct sx150x_chip *chip,
+ int irq_summary,
+ int irq_base)
+{
+ int err;
+ unsigned n;
+ unsigned irq;
+
+ chip->irq_summary = irq_summary;
+ chip->irq_base = irq_base;
+
+ for (n = 0; n < chip->dev_cfg->ngpios; ++n) {
+ irq = irq_base + n;
+ set_irq_chip_and_handler(irq, &chip->irq_chip, handle_edge_irq);
+ set_irq_nested_thread(irq, 1);
+#ifdef CONFIG_ARM
+ set_irq_flags(irq, IRQF_VALID);
+#else
+ set_irq_noprobe(irq);
+#endif
+ }
+
+ err = request_threaded_irq(irq_summary,
+ NULL,
+ sx150x_irq_thread_fn,
+ IRQF_SHARED | IRQF_TRIGGER_FALLING,
+ chip->irq_chip.name,
+ chip);
+ if (err < 0) {
+ chip->irq_summary = -1;
+ chip->irq_base = -1;
+ }
+
+ return err;
+}
+
+static void sx150x_remove_irq_chip(struct sx150x_chip *chip)
+{
+ unsigned n;
+ unsigned irq;
+
+ free_irq(chip->irq_summary, chip);
+
+ for (n = 0; n < chip->dev_cfg->ngpios; ++n) {
+ irq = chip->irq_base + n;
+ set_irq_handler(irq, NULL);
+ set_irq_chip(irq, NULL);
+ }
+}
+
+static int __devinit sx150x_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ static const u32 i2c_funcs = I2C_FUNC_SMBUS_BYTE_DATA |
+ I2C_FUNC_SMBUS_WRITE_WORD_DATA;
+ struct sx150x_platform_data *pdata;
+ struct sx150x_chip *chip;
+ int rc;
+
+ pdata = client->dev.platform_data;
+ if (!pdata)
+ return -EINVAL;
+
+ if (!i2c_check_functionality(client->adapter, i2c_funcs))
+ return -ENOSYS;
+
+ chip = kzalloc(sizeof(struct sx150x_chip), GFP_KERNEL);
+ if (!chip)
+ return -ENOMEM;
+
+ sx150x_init_chip(chip, client, id->driver_data, pdata);
+ rc = sx150x_init_hw(chip, pdata);
+ if (rc < 0)
+ goto probe_fail_pre_gpiochip_add;
+
+ rc = gpiochip_add(&chip->gpio_chip);
+ if (rc < 0)
+ goto probe_fail_pre_gpiochip_add;
+
+ if (pdata->irq_summary >= 0) {
+ rc = sx150x_install_irq_chip(chip,
+ pdata->irq_summary,
+ pdata->irq_base);
+ if (rc < 0)
+ goto probe_fail_post_gpiochip_add;
+ }
+
+ i2c_set_clientdata(client, chip);
+
+ return 0;
+probe_fail_post_gpiochip_add:
+ WARN_ON(gpiochip_remove(&chip->gpio_chip) < 0);
+probe_fail_pre_gpiochip_add:
+ kfree(chip);
+ return rc;
+}
+
+static int __devexit sx150x_remove(struct i2c_client *client)
+{
+ struct sx150x_chip *chip;
+ int rc;
+
+ chip = i2c_get_clientdata(client);
+ rc = gpiochip_remove(&chip->gpio_chip);
+ if (rc < 0)
+ return rc;
+
+ if (chip->irq_summary >= 0)
+ sx150x_remove_irq_chip(chip);
+
+ kfree(chip);
+
+ return 0;
+}
+
+static struct i2c_driver sx150x_driver = {
+ .driver = {
+ .name = "sx150x",
+ .owner = THIS_MODULE
+ },
+ .probe = sx150x_probe,
+ .remove = __devexit_p(sx150x_remove),
+ .id_table = sx150x_id,
+};
+
+static int __init sx150x_init(void)
+{
+ return i2c_add_driver(&sx150x_driver);
+}
+subsys_initcall(sx150x_init);
+
+static void __exit sx150x_exit(void)
+{
+ return i2c_del_driver(&sx150x_driver);
+}
+module_exit(sx150x_exit);
+
+MODULE_AUTHOR("Gregory Bean <gbean@codeaurora.org>");
+MODULE_DESCRIPTION("Driver for Semtech SX150X I2C GPIO Expanders");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("i2c:sx150x");
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-11-23 09:50:11 +0000