diff options
Diffstat (limited to 'drivers/gpio')
| -rw-r--r-- | drivers/gpio/Kconfig | 7 | ||||
| -rw-r--r-- | drivers/gpio/gpio-mcp23s08.c | 192 |
2 files changed, 191 insertions, 8 deletions
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig index 47eae6ea5dd..363498697c2 100644 --- a/drivers/gpio/Kconfig +++ b/drivers/gpio/Kconfig @@ -412,10 +412,11 @@ config GPIO_MAX7301 GPIO driver for Maxim MAX7301 SPI-based GPIO expander. config GPIO_MCP23S08 - tristate "Microchip MCP23Sxx I/O expander" - depends on SPI_MASTER + tristate "Microchip MCP23xxx I/O expander" + depends on SPI_MASTER || I2C help - SPI driver for Microchip MCP23S08/MPC23S17 I/O expanders. + SPI/I2C driver for Microchip MCP23S08/MCP23S17/MCP23008/MCP23017 + I/O expanders. This provides a GPIO interface supporting inputs and outputs. config GPIO_MC33880 diff --git a/drivers/gpio/gpio-mcp23s08.c b/drivers/gpio/gpio-mcp23s08.c index 7b78f940868..1ef46e6c2a2 100644 --- a/drivers/gpio/gpio-mcp23s08.c +++ b/drivers/gpio/gpio-mcp23s08.c @@ -1,11 +1,12 @@ /* - * MCP23S08 SPI gpio expander driver + * MCP23S08 SPI/GPIO gpio expander driver */ #include <linux/kernel.h> #include <linux/device.h> #include <linux/mutex.h> #include <linux/gpio.h> +#include <linux/i2c.h> #include <linux/spi/spi.h> #include <linux/spi/mcp23s08.h> #include <linux/slab.h> @@ -16,13 +17,13 @@ */ #define MCP_TYPE_S08 0 #define MCP_TYPE_S17 1 +#define MCP_TYPE_008 2 +#define MCP_TYPE_017 3 /* Registers are all 8 bits wide. * * The mcp23s17 has twice as many bits, and can be configured to work * with either 16 bit registers or with two adjacent 8 bit banks. - * - * Also, there are I2C versions of both chips. */ #define MCP_IODIR 0x00 /* init/reset: all ones */ #define MCP_IPOL 0x01 @@ -73,6 +74,72 @@ struct mcp23s08_driver_data { struct mcp23s08 chip[]; }; +/*----------------------------------------------------------------------*/ + +#ifdef CONFIG_I2C + +static int mcp23008_read(struct mcp23s08 *mcp, unsigned reg) +{ + return i2c_smbus_read_byte_data(mcp->data, reg); +} + +static int mcp23008_write(struct mcp23s08 *mcp, unsigned reg, unsigned val) +{ + return i2c_smbus_write_byte_data(mcp->data, reg, val); +} + +static int +mcp23008_read_regs(struct mcp23s08 *mcp, unsigned reg, u16 *vals, unsigned n) +{ + while (n--) { + int ret = mcp23008_read(mcp, reg++); + if (ret < 0) + return ret; + *vals++ = ret; + } + + return 0; +} + +static int mcp23017_read(struct mcp23s08 *mcp, unsigned reg) +{ + return i2c_smbus_read_word_data(mcp->data, reg << 1); +} + +static int mcp23017_write(struct mcp23s08 *mcp, unsigned reg, unsigned val) +{ + return i2c_smbus_write_word_data(mcp->data, reg << 1, val); +} + +static int +mcp23017_read_regs(struct mcp23s08 *mcp, unsigned reg, u16 *vals, unsigned n) +{ + while (n--) { + int ret = mcp23017_read(mcp, reg++); + if (ret < 0) + return ret; + *vals++ = ret; + } + + return 0; +} + +static const struct mcp23s08_ops mcp23008_ops = { + .read = mcp23008_read, + .write = mcp23008_write, + .read_regs = mcp23008_read_regs, +}; + +static const struct mcp23s08_ops mcp23017_ops = { + .read = mcp23017_read, + .write = mcp23017_write, + .read_regs = mcp23017_read_regs, +}; + +#endif /* CONFIG_I2C */ + +/*----------------------------------------------------------------------*/ + #ifdef CONFIG_SPI_MASTER static int mcp23s08_read(struct mcp23s08 *mcp, unsigned reg) @@ -331,6 +398,20 @@ static int mcp23s08_probe_one(struct mcp23s08 *mcp, struct device *dev, break; #endif /* CONFIG_SPI_MASTER */ +#ifdef CONFIG_I2C + case MCP_TYPE_008: + mcp->ops = &mcp23008_ops; + mcp->chip.ngpio = 8; + mcp->chip.label = "mcp23008"; + break; + + case MCP_TYPE_017: + mcp->ops = &mcp23017_ops; + mcp->chip.ngpio = 16; + mcp->chip.label = "mcp23017"; + break; +#endif /* CONFIG_I2C */ + default: dev_err(dev, "invalid device type (%d)\n", type); return -EINVAL; @@ -389,6 +470,91 @@ fail: return status; } +/*----------------------------------------------------------------------*/ + +#ifdef CONFIG_I2C + +static int __devinit mcp230xx_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct mcp23s08_platform_data *pdata; + struct mcp23s08 *mcp; + int status; + + pdata = client->dev.platform_data; + if (!pdata || !gpio_is_valid(pdata->base)) { + dev_dbg(&client->dev, "invalid or missing platform data\n"); + return -EINVAL; + } + + mcp = kzalloc(sizeof *mcp, GFP_KERNEL); + if (!mcp) + return -ENOMEM; + + status = mcp23s08_probe_one(mcp, &client->dev, client, client->addr, + id->driver_data, pdata->base, + pdata->chip[0].pullups); + if (status) + goto fail; + + i2c_set_clientdata(client, mcp); + + return 0; + +fail: + kfree(mcp); + + return status; +} + +static int __devexit mcp230xx_remove(struct i2c_client *client) +{ + struct mcp23s08 *mcp = i2c_get_clientdata(client); + int status; + + status = gpiochip_remove(&mcp->chip); + if (status == 0) + kfree(mcp); + + return status; +} + +static const struct i2c_device_id mcp230xx_id[] = { + { "mcp23008", MCP_TYPE_008 }, + { "mcp23017", MCP_TYPE_017 }, + { }, +}; +MODULE_DEVICE_TABLE(i2c, mcp230xx_id); + +static struct i2c_driver mcp230xx_driver = { + .driver = { + .name = "mcp230xx", + .owner = THIS_MODULE, + }, + .probe = mcp230xx_probe, + .remove = __devexit_p(mcp230xx_remove), + .id_table = mcp230xx_id, +}; + +static int __init mcp23s08_i2c_init(void) +{ + return i2c_add_driver(&mcp230xx_driver); +} + +static void mcp23s08_i2c_exit(void) +{ + i2c_del_driver(&mcp230xx_driver); +} + +#else + +static int __init mcp23s08_i2c_init(void) { return 0; } +static void mcp23s08_i2c_exit(void) { } + +#endif /* CONFIG_I2C */ + +/*----------------------------------------------------------------------*/ + #ifdef CONFIG_SPI_MASTER static int mcp23s08_probe(struct spi_device *spi) @@ -525,9 +691,24 @@ static void mcp23s08_spi_exit(void) { } static int __init mcp23s08_init(void) { - return mcp23s08_spi_init(); + int ret; + + ret = mcp23s08_spi_init(); + if (ret) + goto spi_fail; + + ret = mcp23s08_i2c_init(); + if (ret) + goto i2c_fail; + + return 0; + + i2c_fail: + mcp23s08_spi_exit(); + spi_fail: + return ret; } -/* register after spi postcore initcall and before +/* register after spi/i2c postcore initcall and before * subsys initcalls that may rely on these GPIOs */ subsys_initcall(mcp23s08_init); @@ -535,6 +716,7 @@ subsys_initcall(mcp23s08_init); static void __exit mcp23s08_exit(void) { mcp23s08_spi_exit(); + mcp23s08_i2c_exit(); } module_exit(mcp23s08_exit); |