Subject: [PATCH 2/3] wlcore/wl12xx: spi: add device tree support

From: [email-masked] (Uri Mashiach)
Date: Thu, 24 Dec 2015 09:41:34 +0200

Hi Grygorii,

On 12/23/2015 12:25 PM, Grygorii Strashko wrote:
> On 12/23/2015 10:35 AM, Uri Mashiach wrote:
>> Add DT support for the wl1271 SPI WiFi.
>>
>> Add documentation file for the wl1271 SPI WiFi.
>>
>> Signed-off-by: Uri Mashiach <[email-masked]>
>> Acked-by: Igor Grinberg <[email-masked]>
>> ---
>>    .../bindings/net/wireless/ti,wlcore,spi.txt        | 35 +++++++++++
>>    drivers/net/wireless/ti/wlcore/spi.c               | 67 +++++++++++++++++++---
>>    2 files changed, 95 insertions(+), 7 deletions(-)
>>    create mode 100644 Documentation/devicetree/bindings/net/wireless/ti,wlcore,spi.txt
>>
>> diff --git a/Documentation/devicetree/bindings/net/wireless/ti,wlcore,spi.txt b/Documentation/devicetree/bindings/net/wireless/ti,wlcore,spi.txt
>> new file mode 100644
>> index 0000000..a3e7eb7
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/net/wireless/ti,wlcore,spi.txt
>> @@ -0,0 +1,35 @@
>> +* Texas Instruments wl1271 wireless lan controller
>> +
>> +The wl1271 chip can be connected via SPI or via SDIO. This
>> +document describes the binding for the SPI connected chip.
>> +
>> +Required properties:
>> +- compatible :          Should be "ti,wl1271"
>> +- reg :                 Chip select address of device
>> +- spi-max-frequency :   Maximum SPI clocking speed of device in Hz
>> +- ref-clock-frequency : Reference clock frequency
>> +- interrupts :          Should contain interrupt line and trigger type
>
> It's good to describe here number of IRQ lines your device have and IRQ types (edge/level)
>
>> +- interrupt-parent :    Should be the phandle for the interrupt controller
> interrupt-parent is not required (also interrupts-extended can be used)
>
>> +                        that services interrupts for this device
>> +- vwlan-supply :        Point the node of the regulator that controls the wl1271 chip WLAN_EN pin
>
> Pls, use gpio if this is required just to toggle WLAN_EN pin.
>
> [ti,] power-gpio or en-gpio
>
>
>> +
>> +Optional properties:
>> +- clock-xtal :          boolean, clock is generated from XTAL
>> +
>> +- Please consult Documentation/devicetree/bindings/spi/spi-bus.txt
>> +  for optional SPI connection related properties,just
>> +
>> +Examples:
>> +
>> +&spi1 {
>> +	wl1271 at 1 {
>> +		compatible = "ti,wl1271";
>> +
>> +		reg = <1>;
>> +		spi-max-frequency = <48000000>;
>> +		clock-xtal;
>> +		interrupt-parent = <&gpio3>;
>> +		interrupts = <8 IRQ_TYPE_LEVEL_HIGH>;
>> +		wifi-supply = <&wifi_fixed>;
>> +	};
>> +};
>> diff --git a/drivers/net/wireless/ti/wlcore/spi.c b/drivers/net/wireless/ti/wlcore/spi.c
>> index d3a4bcb..7281f5a 100644
>> --- a/drivers/net/wireless/ti/wlcore/spi.c
>> +++ b/drivers/net/wireless/ti/wlcore/spi.c
>> @@ -30,6 +30,7 @@
>>    #include <linux/spi/spi.h>
>>    #include <linux/wl12xx.h>
>>    #include <linux/platform_device.h>
>> +#include <linux/of_irq.h>
>>    #include <linux/regulator/consumer.h>
>>
>>    #include "wlcore.h"
>> @@ -357,6 +358,54 @@ static struct wl1271_if_operations spi_ops = {
>>    	.set_block_size = NULL,
>>    };
>>
>> +#ifdef CONFIG_OF
>> +static const struct of_device_id wlcore_spi_of_match_table[] = {
>> +	{ .compatible = "ti,wl1271" },
>> +	{ }
>> +};
>> +
>> +/**
>> + * wlcore_probe_of - DT node parsing.
>> + * @spi: SPI slave device parameters.
>> + * @res: resource parameters.
>> + * @glue: wl12xx SPI bus to slave device glue parameters.
>> + * @pdev_data: wlcore device parameters
>> + */
>> +static int wlcore_probe_of(struct spi_device *spi, struct resource *res,
>> +			   struct wl12xx_spi_glue *glue,
>> +			   struct wlcore_platdev_data *pdev_data)
>> +{
>> +	struct device_node *dt_node = spi->dev.of_node;
>> +	int ret;
>> +
>> +	ret = of_irq_to_resource(dt_node, 0, &res[0]);
>> +	if (spi->irq != ret) {
>> +		dev_err(glue->dev, "can't get interrupt resource\n");
>> +		return -EINVAL;
>> +	}
>
> SPI core will parse IRQ for you (see below)
>

The IRQ type should be stored in res[0].flags.
Is there an alternative to of_irq_to_resource() for getting the IRQ type?

>> +
>> +	if (of_find_property(dt_node, "clock-xtal", NULL))
>> +		pdev_data->ref_clock_xtal = true;
>> +
>> +	ret = of_property_read_u32(dt_node, "ref-clock-frequency",
>> +				   &pdev_data->ref_clock_freq);
>> +	if (IS_ERR_VALUE(ret)) {
>> +		dev_err(glue->dev,
>> +			"can't get reference clock frequency (%d)\n", ret);
>> +		return ret;
>> +	}
>> +
>> +	return 0;
>> +}
>> +#else /* CONFIG_OF */
>> +static int wlcore_probe_of(struct spi_device *spi, struct resource *res,
>> +			   struct wl12xx_spi_glue *glue,
>> +			   struct wlcore_platdev_data *pdev_data)
>> +{
>> +	return -ENODATA;
>> +}
>> +#endif /* CONFIG_OF */
>> +
>>    static int wl1271_probe(struct spi_device *spi)
>>    {
>>    	struct wl12xx_spi_glue *glue;
>> @@ -365,8 +414,7 @@ static int wl1271_probe(struct spi_device *spi)
>>    	int ret;
>>
>>    	memset(&pdev_data, 0x00, sizeof(pdev_data));
>> -
>> -	/* TODO: add DT parsing when needed */
>> +	memset(res, 0x00, sizeof(res));
>>
>>    	pdev_data.if_ops = &spi_ops;
>>
>> @@ -390,6 +438,13 @@ static int wl1271_probe(struct spi_device *spi)
>>    		return PTR_ERR(glue->reg);
>>    	}
>>
>> +	ret = wlcore_probe_of(spi, &res[0], glue, &pdev_data);
>> +	if (IS_ERR_VALUE(ret)) {
>> +		dev_err(glue->dev,
>> +			"can't get device tree parameters (%d)\n", ret);
>> +		return ret;
>
> So, wl1271_probe will fail always if CONFIG_OF=n. Right?
>
>
>> +	}
>> +
>>    	ret = spi_setup(spi);
>>    	if (ret < 0) {
>>    		dev_err(glue->dev, "spi_setup failed\n");
>> @@ -404,10 +459,6 @@ static int wl1271_probe(struct spi_device *spi)
>>
>>    	glue->core->dev.parent = &spi->dev;
>>
>> -	memset(res, 0x00, sizeof(res));
>> -
>> -	res[0].start = spi->irq;
>> -	res[0].flags = IORESOURCE_IRQ;
>>    	res[0].name = "irq";
>
> Above code might be left unchaenged.
>
>
>>
>>    	ret = platform_device_add_resources(glue->core, res, ARRAY_SIZE(res));
>> @@ -445,10 +496,12 @@ static int wl1271_remove(struct spi_device *spi)
>>    	return 0;
>>    }
>>
>> -
>>    static struct spi_driver wl1271_spi_driver = {
>>    	.driver = {
>>    		.name		= "wl1271_spi",
>> +#ifdef CONFIG_OF
>> +		.of_match_table = of_match_ptr(wlcore_spi_of_match_table),
>> +#endif /* CONFIG_OF */
>
> These ifdefs are not needed - see of_match_ptr() definition
>
>>    	},
>>
>>    	.probe		= wl1271_probe,
>>
>
>

-- 
Thanks,
Uri