Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965145Ab3HHK5f (ORCPT ); Thu, 8 Aug 2013 06:57:35 -0400 Received: from perceval.ideasonboard.com ([95.142.166.194]:43952 "EHLO perceval.ideasonboard.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751467Ab3HHK5d (ORCPT ); Thu, 8 Aug 2013 06:57:33 -0400 From: Laurent Pinchart To: Linus Walleij Cc: linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org Subject: Re: [3/3] gpio: pcf857x: Add OF support Date: Thu, 08 Aug 2013 12:58:38 +0200 Message-ID: <2793476.ZrasnaE7Ld@avalon> User-Agent: KMail/4.10.5 (Linux/3.8.13-gentoo; KDE/4.10.5; x86_64; ; ) In-Reply-To: <1375123145-31648-4-git-send-email-laurent.pinchart+renesas@ideasonboard.com> References: <1375123145-31648-4-git-send-email-laurent.pinchart+renesas@ideasonboard.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 8457 Lines: 212 Hello, I'd like to get this patch set in v3.12. If there's no objection, Linus, could you please take it in your tree ? On Monday 29 July 2013 20:39:05 Laurent Pinchart wrote: > Add DT bindings for the pcf857x-compatible chips and parse the device > tree node in the driver. > > Signed-off-by: Laurent Pinchart > > --- > .../devicetree/bindings/gpio/gpio-pcf857x.txt | 69 ++++++++++++++++++++ > drivers/gpio/gpio-pcf857x.c | 57 +++++++++++++++--- > 2 files changed, 117 insertions(+), 9 deletions(-) > create mode 100644 Documentation/devicetree/bindings/gpio/gpio-pcf857x.txt > > diff --git a/Documentation/devicetree/bindings/gpio/gpio-pcf857x.txt > b/Documentation/devicetree/bindings/gpio/gpio-pcf857x.txt new file mode > 100644 > index 0000000..575b05e > --- /dev/null > +++ b/Documentation/devicetree/bindings/gpio/gpio-pcf857x.txt > @@ -0,0 +1,69 @@ > +* PCF857x-compatible I/O expanders > + > +The PCF857x-compatible chips have "quasi-bidirectional" I/O pins that can > be +driven high by a pull-up current source or driven low to ground. This > combines +the direction and output level into a single bit per pin, which > can't be read +back. We can't actually know at initialization time whether > a pin is configured +(a) as output and driving the signal low/high, or (b) > as input and reporting a +low/high value, without knowing the last value > written since the chip came out +of reset (if any). The only reliable > solution for setting up pin direction is +thus to do it explicitly. > + > +Required Properties: > + > + - compatible: should be one of the following. > + - "maxim,max7328": For the Maxim MAX7378 > + - "maxim,max7329": For the Maxim MAX7329 > + - "nxp,pca8574": For the NXP PCA8574 > + - "nxp,pca8575": For the NXP PCA8575 > + - "nxp,pca9670": For the NXP PCA9670 > + - "nxp,pca9671": For the NXP PCA9671 > + - "nxp,pca9672": For the NXP PCA9672 > + - "nxp,pca9673": For the NXP PCA9673 > + - "nxp,pca9674": For the NXP PCA9674 > + - "nxp,pca9675": For the NXP PCA9675 > + - "nxp,pcf8574": For the NXP PCF8574 > + - "nxp,pcf8574a": For the NXP PCF8574A > + - "nxp,pcf8575": For the NXP PCF8575 > + - "ti,tca9554": For the TI TCA9554 > + > + - reg: I2C slave address. > + > + - gpio-controller: Marks the device node as a gpio controller. > + - #gpio-cells: Should be 2. The first cell is the GPIO number and the > second + cell specifies GPIO flags, as defined in > . Only the + GPIO_ACTIVE_HIGH and > GPIO_ACTIVE_LOW flags are supported. > + > +Optional Properties: > + > + - pins-initial-state: Bitmask that specifies the initial state of each > pin. + When a bit is set to zero, the corresponding pin will be > initialized to the + input (pulled-up) state. When the bit is set to one, > the pin will be + initialized the the low-level output state. If the > property is not specified + all pins will be initialized to the input > state. > + > + The I/O expander can detect input state changes, and thus optionally act > as + an interrupt controller. When interrupts support is desired all the > following + properties must be set. For more information please see the > interrupt + controller device tree bindings documentation available at > + Documentation/devicetree/bindings/interrupt-controller/interrupts.txt. > + > + - interrupt-controller: Identifies the node as an interrupt controller. > + - #interrupt-cells: Number of cells to encode an interrupt source, shall > be 2. + - interrupt-parent: phandle of the parent interrupt controller. + > - interrupts: Interrupt specifier for the controllers interrupt. + > + > +Please refer to gpio.txt in this directory for details of the common GPIO > +bindings used by client devices. > + > +Example: PCF8575 I/O expander node > + > + pcf8575: gpio@20 { > + compatible = "nxp,pcf8575"; > + reg = <0x20>; > + interrupt-parent = <&irqpin2>; > + interrupts = <3 0>; > + interrupt-controller; > + #interrupt-cells = <2>; > + }; > diff --git a/drivers/gpio/gpio-pcf857x.c b/drivers/gpio/gpio-pcf857x.c > index 070e81f..50a90f1 100644 > --- a/drivers/gpio/gpio-pcf857x.c > +++ b/drivers/gpio/gpio-pcf857x.c > @@ -26,6 +26,8 @@ > #include > #include > #include > +#include > +#include > #include > #include > #include > @@ -50,6 +52,27 @@ static const struct i2c_device_id pcf857x_id[] = { > }; > MODULE_DEVICE_TABLE(i2c, pcf857x_id); > > +#ifdef CONFIG_OF > +static const struct of_device_id pcf857x_of_table[] = { > + { .compatible = "nxp,pcf8574", .data = (void *)8 }, > + { .compatible = "nxp,pcf8574a", .data = (void *)8 }, > + { .compatible = "nxp,pca8574", .data = (void *)8 }, > + { .compatible = "nxp,pca9670", .data = (void *)8 }, > + { .compatible = "nxp,pca9672", .data = (void *)8 }, > + { .compatible = "nxp,pca9674", .data = (void *)8 }, > + { .compatible = "nxp,pcf8575", .data = (void *)16 }, > + { .compatible = "nxp,pca8575", .data = (void *)16 }, > + { .compatible = "nxp,pca9671", .data = (void *)16 }, > + { .compatible = "nxp,pca9673", .data = (void *)16 }, > + { .compatible = "nxp,pca9675", .data = (void *)16 }, > + { .compatible = "maxim,max7328", .data = (void *)8 }, > + { .compatible = "maxim,max7329", .data = (void *)8 }, > + { .compatible = "ti,tca9554", .data = (void *)8 }, > + { } > +}; > +MODULE_DEVICE_TABLE(of, pcf857x_of_table); > +#endif > + > /* > * The pcf857x, pca857x, and pca967x chips only expose one read and one > * write register. Writing a "one" bit (to match the reset state) lets > @@ -257,14 +280,29 @@ fail: > static int pcf857x_probe(struct i2c_client *client, > const struct i2c_device_id *id) > { > - struct pcf857x_platform_data *pdata; > + struct pcf857x_platform_data *pdata = client->dev.platform_data; > + struct device_node *np = client->dev.of_node; > struct pcf857x *gpio; > + unsigned int n_latch = 0; > + unsigned int ngpio; > int status; > > - pdata = client->dev.platform_data; > - if (!pdata) { > +#ifdef CONFIG_OF > + if (np) { > + const struct of_device_id *of_id; > + > + of_id = of_match_device(pcf857x_of_table, &client->dev); > + ngpio = (unsigned int)of_id->data; > + } else > +#endif > + ngpio = id->driver_data; > + > + if (pdata) > + n_latch = pdata->n_latch; > + else if (IS_ENABLED(CONFIG_OF) && np) > + of_property_read_u32(np, "pins-initial-state", &n_latch); > + else > dev_dbg(&client->dev, "no platform data\n"); > - } > > /* Allocate, initialize, and register this gpio_chip. */ > gpio = devm_kzalloc(&client->dev, sizeof(*gpio), GFP_KERNEL); > @@ -282,7 +320,7 @@ static int pcf857x_probe(struct i2c_client *client, > gpio->chip.set = pcf857x_set; > gpio->chip.direction_input = pcf857x_input; > gpio->chip.direction_output = pcf857x_output; > - gpio->chip.ngpio = id->driver_data; > + gpio->chip.ngpio = ngpio; > > /* enable gpio_to_irq() if platform has settings */ > if (client->irq) { > @@ -357,11 +395,11 @@ static int pcf857x_probe(struct i2c_client *client, > * may cause transient glitching since it can't know the last value > * written (some pins may need to be driven low). > * > - * Using pdata->n_latch avoids that trouble. When left initialized > - * to zero, our software copy of the "latch" then matches the chip's > - * all-ones reset state. Otherwise it flags pins to be driven low. > + * Using n_latch avoids that trouble. When left initialized to zero, > + * our software copy of the "latch" then matches the chip's all-ones > + * reset state. Otherwise it flags pins to be driven low. > */ > - gpio->out = pdata ? ~pdata->n_latch : ~0; > + gpio->out = ~n_latch; > gpio->status = gpio->out; > > status = gpiochip_add(&gpio->chip); > @@ -423,6 +461,7 @@ static struct i2c_driver pcf857x_driver = { > .driver = { > .name = "pcf857x", > .owner = THIS_MODULE, > + .of_match_table = of_match_ptr(pcf857x_of_table), > }, > .probe = pcf857x_probe, > .remove = pcf857x_remove, -- Regards, Laurent Pinchart -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/