[RFC,1/1] gpio: mcp23s08: convert driver to DT

Message ID	1359647903-15801-2-git-send-email-larsi@wh2.tu-dresden.de (mailing list archive)
State	Superseded, archived
Headers	show Return-Path: <spi-devel-general-bounces@lists.sourceforge.net> From: Lars Poeschel <larsi@wh2.tu-dresden.de> To: poeschel@lemonage.de, grant.likely@secretlab.ca, rob.herring@calxeda.com, rob@landley.net, linus.walleij@linaro.org, devicetree-discuss@lists.ozlabs.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, spi-devel-general@lists.sourceforge.net Subject: [PATCH RFC 1/1] gpio: mcp23s08: convert driver to DT Date: Thu, 31 Jan 2013 16:58:23 +0100 Message-Id: <1359647903-15801-2-git-send-email-larsi@wh2.tu-dresden.de> In-Reply-To: <1359647903-15801-1-git-send-email-larsi@wh2.tu-dresden.de> References: <1359647903-15801-1-git-send-email-larsi@wh2.tu-dresden.de> Cc: w.sang@pengutronix.de, ben-linux@fluff.org, linux-i2c@vger.kernel.org Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: spi-devel-general-bounces@lists.sourceforge.net

diff --git a/Documentation/devicetree/bindings/gpio/gpio-mcp23s08.txt b/Documentation/devicetree/bindings/gpio/gpio-mcp23s08.txt new file mode 100644 index 0000000..572bc87 --- /dev/null +++ b/Documentation/devicetree/bindings/gpio/gpio-mcp23s08.txt @@ -0,0 +1,27 @@ +Microchip MCP2308/MCP23S08/MCP23017/MCP23S17 driver for +8-/16-bit I/O expander with serial interface (I2C/SPI) + +Required properties: +- compatible : Should be "mcp,mcp23s08-gpio", "mcp,mcp23s17-gpio", + "mcp,mcp23008-gpio" or "mcp,mcp23017-gpio" +- base : The first gpio number that should be assigned by this chip. + +Optional properties: +- chips : This is a table with 2 columns and up to 8 entries. The first column + is a is_present flag, that makes only sense for SPI chips. Multiple + chips can share the same chipselect. This flag can be 0 or 1 depending + if there is a chip at this address or not. + The second column is written to the GPPU register, selecting a 100k + pullup resistor or not. Setting a 1 is activating the pullup. + For I2C chips only the first line in this table is used. Further chips + are registered at different addresses at the I2C bus. + +Example: +&mcp0 { + compatible = "mcp,mcp23017"; + base = <128>; + chips = < + /* is_present pullups */ + 1 0x07 /* chip addr 0 */ + >; +}; diff --git a/drivers/gpio/gpio-mcp23s08.c b/drivers/gpio/gpio-mcp23s08.c index 3cea0ea..7f90d11 100644 --- a/drivers/gpio/gpio-mcp23s08.c +++ b/drivers/gpio/gpio-mcp23s08.c @@ -12,6 +12,8 @@ #include <linux/spi/mcp23s08.h> #include <linux/slab.h> #include <asm/byteorder.h> +#include <linux/of.h> +#include <linux/of_device.h> /** * MCP types supported by driver @@ -473,16 +475,89 @@ fail: /*----------------------------------------------------------------------*/ +#ifdef CONFIG_OF +static struct of_device_id mcp23s08_of_match[] = { +#ifdef CONFIG_SPI_MASTER + { + .compatible = "mcp,mcp23s08-gpio", + }, + { + .compatible = "mcp,mcp23s17-gpio", + }, +#endif +#if IS_ENABLED(CONFIG_I2C) + { + .compatible = "mcp,mcp23008-gpio", + }, + { + .compatible = "mcp,mcp23017-gpio", + }, +#endif + { }, +}; +MODULE_DEVICE_TABLE(of, mcp23s08_of_match); + +static struct mcp23s08_platform_data * + of_get_mcp23s08_pdata(struct device *dev) +{ + struct mcp23s08_platform_data *pdata; + struct device_node *np = dev->of_node; + u32 gpio_base; + u32 chips[sizeof(pdata->chip)]; + int ret, i, j; + + pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL); + if (!pdata) + return NULL; + + ret = of_property_read_u32(np, "base", &gpio_base); + if (!ret) + pdata->base = gpio_base; + + for (i = ARRAY_SIZE(pdata->chip) * MCP23S08_CHIP_INFO_MEMBERS; + i > 0; i -= MCP23S08_CHIP_INFO_MEMBERS) { + ret = of_property_read_u32_array(np, "chips", chips, i); + if (ret == -EOVERFLOW) + continue; + break; + } + if (!ret) { + for (j = 0; j < i / MCP23S08_CHIP_INFO_MEMBERS ; j++) { + pdata->chip[j].is_present = + chips[j * MCP23S08_CHIP_INFO_MEMBERS]; + pdata->chip[j].pullups = + chips[j * MCP23S08_CHIP_INFO_MEMBERS + 1]; + } + } + + return pdata; +} +#else +static struct mcp23s08_platform_data * + of_get_mcp23s08_pdata(struct i2c_client *client, int *chip_id) +{ + return NULL; +} +#endif /* CONFIG_OF */ + #if IS_ENABLED(CONFIG_I2C) static int mcp230xx_probe(struct i2c_client *client, const struct i2c_device_id *id) { - struct mcp23s08_platform_data *pdata; + struct mcp23s08_platform_data *pdata = NULL; struct mcp23s08 *mcp; int status; + const struct of_device_id *match; + + match = of_match_device(of_match_ptr(mcp23s08_of_match), &client->dev); + if (match) + pdata = of_get_mcp23s08_pdata(&client->dev); + + /* if there was no pdata in DT, take it the legacy way */ + if (!pdata) + pdata = client->dev.platform_data; - pdata = client->dev.platform_data; if (!pdata || !gpio_is_valid(pdata->base)) { dev_dbg(&client->dev, "invalid or missing platform data\n"); return -EINVAL; @@ -531,6 +606,7 @@ static struct i2c_driver mcp230xx_driver = { .driver = { .name = "mcp230xx", .owner = THIS_MODULE, + .of_match_table = mcp23s08_of_match, }, .probe = mcp230xx_probe, .remove = mcp230xx_remove, @@ -560,16 +636,24 @@ static void mcp23s08_i2c_exit(void) { } static int mcp23s08_probe(struct spi_device *spi) { - struct mcp23s08_platform_data *pdata; + struct mcp23s08_platform_data *pdata = NULL; unsigned addr; unsigned chips = 0; struct mcp23s08_driver_data *data; int status, type; unsigned base; + const struct of_device_id *match; type = spi_get_device_id(spi)->driver_data; - pdata = spi->dev.platform_data; + match = of_match_device(of_match_ptr(mcp23s08_of_match), &spi->dev); + if (match) + pdata = of_get_mcp23s08_pdata(&spi->dev); + + /* if there was no pdata in DT, take it the legacy way */ + if (!pdata) + pdata = spi->dev.platform_data; + if (!pdata || !gpio_is_valid(pdata->base)) { dev_dbg(&spi->dev, "invalid or missing platform data\n"); return -EINVAL; @@ -668,6 +752,7 @@ static struct spi_driver mcp23s08_driver = { .driver = { .name = "mcp23s08", .owner = THIS_MODULE, + .of_match_table = mcp23s08_of_match, }, }; diff --git a/include/linux/spi/mcp23s08.h b/include/linux/spi/mcp23s08.h index 2d676d5..3969e12 100644 --- a/include/linux/spi/mcp23s08.h +++ b/include/linux/spi/mcp23s08.h @@ -1,3 +1,4 @@ +#define MCP23S08_CHIP_INFO_MEMBERS 2 /* FIXME driver should be able to handle IRQs... */

[RFC,1/1] gpio: mcp23s08: convert driver to DT

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