[PATCH 1/5 v3] i2c/gpio: add DT support
Jean-Christophe PLAGNIOL-VILLARD
plagnioj at jcrosoft.com
Tue Mar 13 05:11:04 EDT 2012
On 08:37 Tue 13 Mar , Wolfram Sang wrote:
> On Thu, Mar 08, 2012 at 09:50:31AM +0100, Jean-Christophe PLAGNIOL-VILLARD wrote:
> > Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj at jcrosoft.com>
> > Cc: Nicolas Ferre <nicolas.ferre at atmel.com>
> > Cc: linux-i2c at vger.kernel.org
> > Cc: devicetree-discuss at lists.ozlabs.org
>
> Your patch description says "add DT support" but you are doing a bit more.
> This should at least be described here.
>
> > ---
> > v3:
> >
> > update i2c binding (Rob comments)
> >
> > Jean can I have a ack to apply it?
> >
> > Best Regards,
> > J.
> > .../devicetree/bindings/gpio/gpio_i2c.txt | 32 +++++++
> > drivers/i2c/busses/i2c-gpio.c | 94 +++++++++++++++----
> > 2 files changed, 106 insertions(+), 20 deletions(-)
> > create mode 100644 Documentation/devicetree/bindings/gpio/gpio_i2c.txt
> >
> > diff --git a/Documentation/devicetree/bindings/gpio/gpio_i2c.txt b/Documentation/devicetree/bindings/gpio/gpio_i2c.txt
> > new file mode 100644
> > index 0000000..4f8ec94
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/gpio/gpio_i2c.txt
> > @@ -0,0 +1,32 @@
> > +Device-Tree bindings for i2c gpio driver
> > +
> > +Required properties:
> > + - compatible = "i2c-gpio";
>
> I assume people at "devicetree-discuss" have taken care of that, yet I wonder
> that this breaks the "vendor,product" syntax I know of for compatible entries.
yes but there no vendor here
get ack from Grant and Rob
>
> > + - gpios: sda and scl gpio
> > +
> > +
> > +Optional properties:
> > + - i2c-gpio,sda-open-drain: sda as open drain
> > + - i2c-gpio,scl-open-drain: scl as open drain
> > + - i2c-gpio,scl-output-only: scl as output only
> > + - i2c-gpio,delay-us: delay between GPIO operations (may depend on each platform)
> > + - i2c-gpio,timeout-ms: timeout to get data
> > +
> > +Example nodes:
> > +
> > +i2c at 0 {
> > + compatible = "i2c-gpio";
> > + gpios = <&pioA 23 0 /* sda */
> > + &pioA 24 0 /* scl */
> > + >;
> > + i2c-gpio,sda-open-drain;
> > + i2c-gpio,scl-open-drain;
> > + i2c-gpio,delay-us = <2>; /* ~100 kHz */
> > + #address-cells = <1>;
> > + #size-cells = <0>;
> > +
> > + rv3029c2 at 56 {
> > + compatible = "rv3029c2";
> > + reg = <0x56>;
> > + };
> > +};
> > diff --git a/drivers/i2c/busses/i2c-gpio.c b/drivers/i2c/busses/i2c-gpio.c
> > index a651779..98ae85b 100644
> > --- a/drivers/i2c/busses/i2c-gpio.c
> > +++ b/drivers/i2c/busses/i2c-gpio.c
> > @@ -14,8 +14,15 @@
> > #include <linux/module.h>
> > #include <linux/slab.h>
> > #include <linux/platform_device.h>
> > +#include <linux/gpio.h>
> > +#include <linux/of_gpio.h>
> > +#include <linux/of_i2c.h>
> >
> > -#include <asm/gpio.h>
> > +struct i2c_gpio_private_data {
> > + struct i2c_adapter adap;
> > + struct i2c_algo_bit_data bit_data;
> > + struct i2c_gpio_platform_data pdata;
> > +};
> >
> > /* Toggle SDA by changing the direction of the pin */
> > static void i2c_gpio_setsda_dir(void *data, int state)
> > @@ -78,24 +85,62 @@ static int i2c_gpio_getscl(void *data)
> > return gpio_get_value(pdata->scl_pin);
> > }
> >
> > +static int __devinit of_i2c_gpio_probe(struct device_node *np,
> > + struct i2c_gpio_platform_data *pdata)
> > +{
> > + u32 reg;
> > +
> > + if (of_gpio_count(np) < 2)
> > + return -ENODEV;
> > +
> > + pdata->sda_pin = of_get_gpio(np, 0);
> > + pdata->scl_pin = of_get_gpio(np, 1);
> > +
> > + if (pdata->sda_pin < 0 || pdata->scl_pin < 0) {
>
> gpio_is_valid()?
>
> > + pr_err("%s: invalid GPIO pins, sda=%d/scl=%d\n",
> > + np->full_name, pdata->sda_pin, pdata->scl_pin);
> > + return -ENODEV;
> > + }
> > +
> > + of_property_read_u32(np, "i2c-gpio,delay-us", &pdata->udelay);
> > +
> > + if (of_property_read_u32(np, "i2c-gpio,timeout-ms", ®))
> > + pdata->timeout = msecs_to_jiffies(reg);
> > +
> > + pdata->sda_is_open_drain =
> > + !!of_property_read_bool(np, "i2c-gpio,sda-open-drain");
> > + pdata->scl_is_open_drain =
> > + !!of_property_read_bool(np, "i2c-gpio,scl-open-drain");
> > + pdata->scl_is_output_only =
> > + !!of_property_read_bool(np, "i2c-gpio,scl-output-only");
> > +
> > + return 0;
> > +}
> > +
> > static int __devinit i2c_gpio_probe(struct platform_device *pdev)
> > {
> > + struct i2c_gpio_private_data *priv;
> > struct i2c_gpio_platform_data *pdata;
> > struct i2c_algo_bit_data *bit_data;
> > struct i2c_adapter *adap;
> > int ret;
> >
> > - pdata = pdev->dev.platform_data;
> > - if (!pdata)
> > - return -ENXIO;
> > + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
> > + if (!priv)
> > + return -ENOMEM;
> > + adap = &priv->adap;
> > + bit_data = &priv->bit_data;
> > + pdata = &priv->pdata;
> >
> > - ret = -ENOMEM;
> > - adap = kzalloc(sizeof(struct i2c_adapter), GFP_KERNEL);
> > - if (!adap)
> > - goto err_alloc_adap;
> > - bit_data = kzalloc(sizeof(struct i2c_algo_bit_data), GFP_KERNEL);
> > - if (!bit_data)
> > - goto err_alloc_bit_data;
> > + if (pdev->dev.of_node) {
> > + ret = of_i2c_gpio_probe(pdev->dev.of_node, pdata);
> > + if (ret)
> > + return ret;
> > + } else {
> > + if (!pdev->dev.platform_data)
> > + return -ENXIO;
> > + memcpy(pdata, pdev->dev.platform_data, sizeof(*pdata));
> > + }
> >
> > ret = gpio_request(pdata->sda_pin, "sda");
> > if (ret)
> > @@ -143,6 +188,7 @@ static int __devinit i2c_gpio_probe(struct platform_device *pdev)
> > adap->algo_data = bit_data;
> > adap->class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
> > adap->dev.parent = &pdev->dev;
> > + adap->dev.of_node = pdev->dev.of_node;
> >
> > /*
> > * If "dev->id" is negative we consider it as zero.
> > @@ -154,7 +200,9 @@ static int __devinit i2c_gpio_probe(struct platform_device *pdev)
> > if (ret)
> > goto err_add_bus;
> >
> > - platform_set_drvdata(pdev, adap);
> > + of_i2c_register_devices(adap);
> > +
> > + platform_set_drvdata(pdev, priv);
> >
> > dev_info(&pdev->dev, "using pins %u (SDA) and %u (SCL%s)\n",
> > pdata->sda_pin, pdata->scl_pin,
> > @@ -168,34 +216,40 @@ err_add_bus:
> > err_request_scl:
> > gpio_free(pdata->sda_pin);
> > err_request_sda:
> > - kfree(bit_data);
> > -err_alloc_bit_data:
> > - kfree(adap);
> > -err_alloc_adap:
> > return ret;
> > }
> >
> > static int __devexit i2c_gpio_remove(struct platform_device *pdev)
> > {
> > + struct i2c_gpio_private_data *priv;
> > struct i2c_gpio_platform_data *pdata;
> > struct i2c_adapter *adap;
> >
> > - adap = platform_get_drvdata(pdev);
> > - pdata = pdev->dev.platform_data;
> > + priv = platform_get_drvdata(pdev);
> > + adap = &priv->adap;
> > + pdata = &priv->pdata;
> >
> > i2c_del_adapter(adap);
> > gpio_free(pdata->scl_pin);
> > gpio_free(pdata->sda_pin);
> > - kfree(adap->algo_data);
> > - kfree(adap);
> >
> > return 0;
> > }
> >
> > +#if defined(CONFIG_OF)
> > +static const struct of_device_id i2c_gpio_dt_ids[] = {
> > + { .compatible = "i2c-gpio", },
> > + { /* sentinel */ }
> > +};
> > +
> > +MODULE_DEVICE_TABLE(of, i2c_gpio_dt_ids);
> > +#endif
> > +
> > static struct platform_driver i2c_gpio_driver = {
> > .driver = {
> > .name = "i2c-gpio",
> > .owner = THIS_MODULE,
> > + .of_match_table = of_match_ptr(i2c_gpio_dt_ids),
> > },
> > .probe = i2c_gpio_probe,
> > .remove = __devexit_p(i2c_gpio_remove),
>
> Otherwise looks good in general. What was your test scenario?
AT91 support on 3 different SoC
will update and send it via AT91 with your ack
Best Regards,
J.
>
> Thanks,
>
> Wolfram
>
> --
> Pengutronix e.K. | Wolfram Sang |
> Industrial Linux Solutions | http://www.pengutronix.de/ |
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