Re: [PATCH] gpio: Add support for SX151x SPI GPIO Expanders

From: David Brown
Date: Tue Nov 12 2013 - 16:53:15 EST

On Tue, Nov 12, 2013 at 08:32:20PM +0100, Linus Walleij wrote:
Gregory,

this is your driver, can you take a look at this patch?

I don't think Gregory has this email address any more, and I don't
know another address for him.

David

Yours,
Linus Walleij


On Thu, Oct 24, 2013 at 11:51 AM, Viktar Palstsiuk
<viktar.palstsiuk@xxxxxxxxxxx> wrote:

Isolated i2c specific parts and
added spi bindings for the sx151x devices.

Signed-off-by: Viktar Palstsiuk <viktar.palstsiuk@xxxxxxxxxxx>
---
drivers/gpio/Kconfig | 10 +-
drivers/gpio/gpio-sx150x.c | 267 +++++++++++++++++++++++++++++++++++++++------
2 files changed, 239 insertions(+), 38 deletions(-)

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index b6ed304..4d296ab 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -465,15 +465,15 @@ config GPIO_RC5T583
of RC5T583 device through standard gpio library.

config GPIO_SX150X
- bool "Semtech SX150x I2C GPIO expander"
- depends on I2C=y
+ bool "Semtech SX15xx I2C/SPI GPIO expander"
+ depends on SPI_MASTER || I2C
default n
help
- Say yes here to provide support for Semtech SX150-series I2C
+ Say yes here to provide support for Semtech SX15xx-series I2C/SPI
GPIO expanders. Compatible models include:

- 8 bits: sx1508q
- 16 bits: sx1509q
+ 8 bits: sx1508q, sx1511
+ 16 bits: sx1509q, sx1512

config GPIO_STMPE
bool "STMPE GPIOs"
diff --git a/drivers/gpio/gpio-sx150x.c b/drivers/gpio/gpio-sx150x.c
index d2983e9..bee1661 100644
--- a/drivers/gpio/gpio-sx150x.c
+++ b/drivers/gpio/gpio-sx150x.c
@@ -22,9 +22,16 @@
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/slab.h>
+#include <linux/spi/spi.h>
#include <linux/workqueue.h>
#include <linux/i2c/sx150x.h>

+/**
+ * SX15xx types supported by driver
+ */
+#define SX15_TYPE_8_GPIOS 0
+#define SX15_TYPE_16_GPIOS 1
+
#define NO_UPDATE_PENDING -1

struct sx150x_device_data {
@@ -43,9 +50,17 @@ struct sx150x_device_data {
u8 ngpios;
};

+struct sx150x_chip;
+
+struct sx15xx_ops {
+ s32 (*read)(struct device *dev, u8 reg, u8 *val);
+ s32 (*write)(struct device *dev, u8 reg, u8 val);
+};
+
struct sx150x_chip {
struct gpio_chip gpio_chip;
- struct i2c_client *client;
+ struct device *dev;
+ const struct sx15xx_ops *ops;
const struct sx150x_device_data *dev_cfg;
int irq_summary;
int irq_base;
@@ -59,7 +74,7 @@ struct sx150x_chip {
};

static const struct sx150x_device_data sx150x_devices[] = {
- [0] = { /* sx1508q */
+ [SX15_TYPE_8_GPIOS] = { /* sx1508q */
.reg_pullup = 0x03,
.reg_pulldn = 0x04,
.reg_drain = 0x05,
@@ -74,7 +89,7 @@ static const struct sx150x_device_data sx150x_devices[] = {
.reg_reset = 0x7d,
.ngpios = 8
},
- [1] = { /* sx1509q */
+ [SX15_TYPE_16_GPIOS] = { /* sx1509q */
.reg_pullup = 0x07,
.reg_pulldn = 0x09,
.reg_drain = 0x0b,
@@ -91,37 +106,86 @@ static const struct sx150x_device_data sx150x_devices[] = {
},
};

-static const struct i2c_device_id sx150x_id[] = {
- {"sx1508q", 0},
- {"sx1509q", 1},
- {}
-};
-MODULE_DEVICE_TABLE(i2c, sx150x_id);
+#ifdef CONFIG_I2C

-static s32 sx150x_i2c_write(struct i2c_client *client, u8 reg, u8 val)
+static s32 sx150x_i2c_write(struct device *dev, u8 reg, u8 val)
{
+ struct i2c_client *client = to_i2c_client(dev);
s32 err = i2c_smbus_write_byte_data(client, reg, val);

if (err < 0)
- dev_warn(&client->dev,
+ dev_warn(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)
+static s32 sx150x_i2c_read(struct device *dev, u8 reg, u8 *val)
{
+ struct i2c_client *client = to_i2c_client(dev);
s32 err = i2c_smbus_read_byte_data(client, reg);

if (err >= 0)
*val = err;
else
- dev_warn(&client->dev,
+ dev_warn(dev,
"i2c read fail: can't read from %02x: %d\n",
reg, err);
return err;
}

+static const struct sx15xx_ops sx150x_ops = {
+ .read = sx150x_i2c_read,
+ .write = sx150x_i2c_write,
+};
+
+#endif /* CONFIG_I2C */
+
+#ifdef CONFIG_SPI_MASTER
+
+static s32 sx151x_spi_write(struct device *dev, u8 reg, u8 val)
+{
+ struct spi_device *spi = to_spi_device(dev);
+ u8 tx[2];
+ s32 err;
+
+ tx[0] = reg;
+ tx[1] = val;
+
+ err = spi_write(spi, tx, sizeof tx);
+
+ if (err < 0)
+ dev_warn(dev,
+ "spi write fail: can't write %02x to %02x: %d\n",
+ val, reg, err);
+ return err;
+}
+
+static s32 sx151x_spi_read(struct device *dev, u8 reg, u8 *val)
+{
+ struct spi_device *spi = to_spi_device(dev);
+ u8 tx[1], rx[1];
+ s32 err;
+
+ tx[0] = reg | 0x80;
+ err = spi_write_then_read(spi, tx, sizeof tx, rx, sizeof rx);
+
+ if (err >= 0)
+ *val = rx[0];
+ else
+ dev_warn(dev,
+ "spi read fail: can't read from %02x: %d\n",
+ reg, err);
+ return err;
+}
+
+static const struct sx15xx_ops sx151x_ops = {
+ .read = sx151x_spi_read,
+ .write = sx151x_spi_write,
+};
+
+#endif /* CONFIG_SPI_MASTER */
+
static inline bool offset_is_oscio(struct sx150x_chip *chip, unsigned offset)
{
return (chip->dev_cfg->ngpios == offset);
@@ -164,13 +228,12 @@ static s32 sx150x_write_cfg(struct sx150x_chip *chip,
s32 err;

sx150x_find_cfg(offset, width, &reg, &mask, &shift);
- err = sx150x_i2c_read(chip->client, reg, &data);
+ err = chip->ops->read(chip->dev, reg, &data);
if (err < 0)
return err;
-
data &= ~mask;
data |= (val << shift) & mask;
- return sx150x_i2c_write(chip->client, reg, data);
+ return chip->ops->write(chip->dev, reg, data);
}

static int sx150x_get_io(struct sx150x_chip *chip, unsigned offset)
@@ -182,7 +245,7 @@ static int sx150x_get_io(struct sx150x_chip *chip, unsigned offset)
s32 err;

sx150x_find_cfg(offset, 1, &reg, &mask, &shift);
- err = sx150x_i2c_read(chip->client, reg, &data);
+ err = chip->ops->read(chip->dev, reg, &data);
if (err >= 0)
err = (data & mask) != 0 ? 1 : 0;

@@ -191,7 +254,7 @@ static int sx150x_get_io(struct sx150x_chip *chip, unsigned offset)

static void sx150x_set_oscio(struct sx150x_chip *chip, int val)
{
- sx150x_i2c_write(chip->client,
+ chip->ops->write(chip->dev,
chip->dev_cfg->reg_clock,
(val ? 0x1f : 0x10));
}
@@ -361,13 +424,13 @@ static irqreturn_t sx150x_irq_thread_fn(int irq, void *dev_id)
int i;

for (i = (chip->dev_cfg->ngpios / 8) - 1; i >= 0; --i) {
- err = sx150x_i2c_read(chip->client,
+ err = chip->ops->read(chip->dev,
chip->dev_cfg->reg_irq_src - i,
&val);
if (err < 0)
continue;

- sx150x_i2c_write(chip->client,
+ chip->ops->write(chip->dev,
chip->dev_cfg->reg_irq_src - i,
val);
for (n = 0; n < 8; ++n) {
@@ -421,15 +484,17 @@ out:
}

static void sx150x_init_chip(struct sx150x_chip *chip,
- struct i2c_client *client,
+ struct device *dev,
+ const struct sx15xx_ops *ops,
kernel_ulong_t driver_data,
struct sx150x_platform_data *pdata)
{
mutex_init(&chip->lock);

- chip->client = client;
+ chip->dev = dev;
+ chip->ops = ops;
chip->dev_cfg = &sx150x_devices[driver_data];
- chip->gpio_chip.label = client->name;
+ chip->gpio_chip.label = dev_name(dev);
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;
@@ -441,7 +506,7 @@ static void sx150x_init_chip(struct sx150x_chip *chip,
if (pdata->oscio_is_gpo)
++chip->gpio_chip.ngpio;

- chip->irq_chip.name = client->name;
+ chip->irq_chip.name = dev_name(dev);
chip->irq_chip.irq_mask = sx150x_irq_mask;
chip->irq_chip.irq_unmask = sx150x_irq_unmask;
chip->irq_chip.irq_set_type = sx150x_irq_set_type;
@@ -462,7 +527,7 @@ static int sx150x_init_io(struct sx150x_chip *chip, u8 base, u16 cfg)
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));
+ err = chip->ops->write(chip->dev, base - n, cfg >> (n * 8));
return err;
}

@@ -470,13 +535,13 @@ static int sx150x_reset(struct sx150x_chip *chip)
{
int err;

- err = i2c_smbus_write_byte_data(chip->client,
+ err = chip->ops->write(chip->dev,
chip->dev_cfg->reg_reset,
0x12);
if (err < 0)
return err;

- err = i2c_smbus_write_byte_data(chip->client,
+ err = chip->ops->write(chip->dev,
chip->dev_cfg->reg_reset,
0x34);
return err;
@@ -493,7 +558,7 @@ static int sx150x_init_hw(struct sx150x_chip *chip,
return err;
}

- err = sx150x_i2c_write(chip->client,
+ err = chip->ops->write(chip->dev,
chip->dev_cfg->reg_misc,
0x01);
if (err < 0)
@@ -548,7 +613,7 @@ static int sx150x_install_irq_chip(struct sx150x_chip *chip,
#endif
}

- err = devm_request_threaded_irq(&chip->client->dev,
+ err = devm_request_threaded_irq(chip->dev,
irq_summary,
NULL,
sx150x_irq_thread_fn,
@@ -574,6 +639,8 @@ static void sx150x_remove_irq_chip(struct sx150x_chip *chip)
}
}

+#ifdef CONFIG_I2C
+
static int sx150x_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
@@ -595,7 +662,7 @@ static int sx150x_probe(struct i2c_client *client,
if (!chip)
return -ENOMEM;

- sx150x_init_chip(chip, client, id->driver_data, pdata);
+ sx150x_init_chip(chip, &client->dev, &sx150x_ops, id->driver_data, pdata);
rc = sx150x_init_hw(chip, pdata);
if (rc < 0)
return rc;
@@ -636,6 +703,13 @@ static int sx150x_remove(struct i2c_client *client)
return 0;
}

+static const struct i2c_device_id sx150x_id[] = {
+ {"sx1508q", SX15_TYPE_8_GPIOS},
+ {"sx1509q", SX15_TYPE_16_GPIOS},
+ {}
+};
+MODULE_DEVICE_TABLE(i2c, sx150x_id);
+
static struct i2c_driver sx150x_driver = {
.driver = {
.name = "sx150x",
@@ -646,19 +720,146 @@ static struct i2c_driver sx150x_driver = {
.id_table = sx150x_id,
};

-static int __init sx150x_init(void)
+static int __init sx150x_i2c_init(void)
{
return i2c_add_driver(&sx150x_driver);
}
+
+static void __exit sx150x_i2c_exit(void)
+{
+ return i2c_del_driver(&sx150x_driver);
+}
+
+#else
+
+static int __init sx150x_i2c_init(void) { return 0; }
+static void sx150x_i2c_exit(void) { }
+
+#endif /* CONFIG_I2C */
+
+#ifdef CONFIG_SPI_MASTER
+
+static int sx151x_probe(struct spi_device *spi)
+{
+ struct sx150x_platform_data *pdata;
+ struct sx150x_chip *chip;
+ int rc;
+
+ pdata = dev_get_platdata(&spi->dev);
+ if (!pdata) {
+ return -EINVAL;
+ }
+
+ chip = devm_kzalloc(&spi->dev,
+ sizeof(struct sx150x_chip), GFP_KERNEL);
+ if (!chip)
+ return -ENOMEM;
+
+ sx150x_init_chip(chip, &spi->dev, &sx151x_ops,
+ spi_get_device_id(spi)->driver_data, pdata);
+ rc = sx150x_init_hw(chip, pdata);
+ if (rc < 0)
+ return rc;
+
+ rc = gpiochip_add(&chip->gpio_chip);
+ if (rc < 0)
+ return rc;
+
+ 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;
+ }
+
+ spi_set_drvdata(spi, chip);
+
+ return 0;
+probe_fail_post_gpiochip_add:
+ WARN_ON(gpiochip_remove(&chip->gpio_chip) < 0);
+ return rc;
+}
+
+static int sx151x_remove(struct spi_device *spi)
+{
+ struct sx150x_chip *chip;
+ int rc;
+
+ chip = spi_get_drvdata(spi);
+ rc = gpiochip_remove(&chip->gpio_chip);
+ if (rc < 0)
+ return rc;
+
+ if (chip->irq_summary >= 0)
+ sx150x_remove_irq_chip(chip);
+
+ return 0;
+}
+
+static const struct spi_device_id sx151x_ids[] = {
+ { "sx1511", SX15_TYPE_8_GPIOS },
+ { "sx1512", SX15_TYPE_16_GPIOS },
+ { },
+};
+MODULE_DEVICE_TABLE(spi, sx151x_ids);
+
+static struct spi_driver sx151x_driver = {
+ .probe = sx151x_probe,
+ .remove = sx151x_remove,
+ .id_table = sx151x_ids,
+ .driver = {
+ .name = "sx151x",
+ .owner = THIS_MODULE,
+ },
+};
+
+static int __init sx151x_spi_init(void)
+{
+ return spi_register_driver(&sx151x_driver);
+}
+
+static void sx151x_spi_exit(void)
+{
+ spi_unregister_driver(&sx151x_driver);
+}
+
+#else
+
+static int __init sx151x_spi_init(void) { return 0; }
+static void sx151x_spi_exit(void) { }
+
+#endif /* CONFIG_SPI_MASTER */
+
+static int __init sx150x_init(void)
+{
+ int ret;
+
+ ret = sx151x_spi_init();
+ if (ret)
+ goto spi_fail;
+
+ ret = sx150x_i2c_init();
+ if (ret)
+ goto i2c_fail;
+
+ return 0;
+
+ i2c_fail:
+ sx151x_spi_exit();
+ spi_fail:
+ return ret;
+}
subsys_initcall(sx150x_init);

static void __exit sx150x_exit(void)
{
- return i2c_del_driver(&sx150x_driver);
+ sx151x_spi_exit();
+ sx150x_i2c_exit();
}
module_exit(sx150x_exit);

MODULE_AUTHOR("Gregory Bean <gbean@xxxxxxxxxxxxxx>");
-MODULE_DESCRIPTION("Driver for Semtech SX150X I2C GPIO Expanders");
+MODULE_DESCRIPTION("Driver for Semtech SX15xx I2C/SPI GPIO Expanders");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("i2c:sx150x");
--
1.8.4.rc3


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