diff mbox

[1/2] spi: rockchip: add support for "cs-gpios" dts property

Message ID 1497248057-16550-1-git-send-email-jeffy.chen@rock-chips.com (mailing list archive)
State New, archived
Headers show

Commit Message

Jeffy Chen June 12, 2017, 6:14 a.m. UTC
Support using "cs-gpios" property to specify cs gpios.

Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
---

 .../devicetree/bindings/spi/spi-rockchip.txt       |  2 +
 drivers/spi/spi-rockchip.c                         | 52 ++++++++++++++++++++++
 2 files changed, 54 insertions(+)

Comments

Shawn Lin June 12, 2017, 7:15 a.m. UTC | #1
Hi Jeffy,

On 2017/6/12 14:14, Jeffy Chen wrote:
> Support using "cs-gpios" property to specify cs gpios.
> 
> Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
> ---
> 
>   .../devicetree/bindings/spi/spi-rockchip.txt       |  2 +
>   drivers/spi/spi-rockchip.c                         | 52 ++++++++++++++++++++++
>   2 files changed, 54 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/spi/spi-rockchip.txt b/Documentation/devicetree/bindings/spi/spi-rockchip.txt
> index 83da493..02171b2 100644
> --- a/Documentation/devicetree/bindings/spi/spi-rockchip.txt
> +++ b/Documentation/devicetree/bindings/spi/spi-rockchip.txt

The changes for doc should be another patch, and...

> @@ -17,6 +17,7 @@ Required Properties:
>          region.
>   - interrupts: The interrupt number to the cpu. The interrupt specifier format
>                 depends on the interrupt controller.
> +- cs-gpios : Specifies the gpio pins to be used for chipselects.

It's not a required property, otherwise how other boards work as your
patch 2 only add this for rk3399-gru.

>   - clocks: Must contain an entry for each entry in clock-names.
>   - clock-names: Shall be "spiclk" for the transfer-clock, and "apb_pclk" for
>   			   the peripheral clock.
> @@ -48,6 +49,7 @@ Example:
>   		#address-cells = <1>;
>   		#size-cells = <0>;
>   		interrupts = <GIC_SPI 44 IRQ_TYPE_LEVEL_HIGH>;
> +		cs-gpios = <&gpio2 23 GPIO_ACTIVE_HIGH>;
>   		clocks = <&cru SCLK_SPI0>, <&cru PCLK_SPI0>;
>   		clock-names = "spiclk", "apb_pclk";
>   		pinctrl-0 = <&spi1_pins>;
> diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c
> index acf31f3..04694e1 100644
> --- a/drivers/spi/spi-rockchip.c
> +++ b/drivers/spi/spi-rockchip.c
> @@ -15,6 +15,7 @@
>   
>   #include <linux/clk.h>
>   #include <linux/dmaengine.h>
> +#include <linux/gpio.h>
>   #include <linux/module.h>
>   #include <linux/of.h>
>   #include <linux/pinctrl/consumer.h>
> @@ -201,6 +202,10 @@ struct rockchip_spi {
>   	struct dma_slave_caps dma_caps;
>   };
>   
> +struct rockchip_spi_data {
> +	bool cs_gpio_requested;
> +};
> +

Could you fold cs_gpio_requested into struct rockchip_spi?

>   static inline void spi_enable_chip(struct rockchip_spi *rs, int enable)
>   {
>   	writel_relaxed((enable ? 1 : 0), rs->regs + ROCKCHIP_SPI_SSIENR);
> @@ -297,6 +302,50 @@ static void rockchip_spi_set_cs(struct spi_device *spi, bool enable)
>   	pm_runtime_put_sync(rs->dev);
>   }
>   
> +static int rockchip_spi_setup(struct spi_device *spi)
> +{
> +	int ret = 0;
> +	unsigned long flags = (spi->mode & SPI_CS_HIGH) ?
> +			      GPIOF_OUT_INIT_LOW : GPIOF_OUT_INIT_HIGH;
> +	struct rockchip_spi_data *data = spi_get_ctldata(spi);
> +
> +	if (!gpio_is_valid(spi->cs_gpio))
> +		return 0;

return -EINVAL?

> +
> +	if (!data) {
> +		data = kzalloc(sizeof(*data), GFP_KERNEL);
> +		if (!data)
> +			return -ENOMEM;
> +		spi_set_ctldata(spi, data);
> +	}
> +
> +	if (!data->cs_gpio_requested) {
> +		ret = gpio_request_one(spi->cs_gpio, flags,
> +				       dev_name(&spi->dev));
> +		if (!ret)
> +			data->cs_gpio_requested = 1;
> +	} else
> +		ret = gpio_direction_output(spi->cs_gpio, flags);

need brace around 'else' statement. Also I don't see data used
elsewhere, so you need these code above.

> +
> +	if (ret < 0)
> +		dev_err(&spi->dev, "Failed to setup cs gpio(%d): %d\n",
> +			spi->cs_gpio, ret);
> +
> +	return ret;
> +}
> +
> +static void rockchip_spi_cleanup(struct spi_device *spi)
> +{
> +	struct rockchip_spi_data *data = spi_get_ctldata(spi);
> +
> +	if (data) {
> +		if (data->cs_gpio_requested)
> +			gpio_free(spi->cs_gpio);
> +		kfree(data);
> +		spi_set_ctldata(spi, NULL);
> +	}
> +}
> +
>   static int rockchip_spi_prepare_message(struct spi_master *master,
>   					struct spi_message *msg)
>   {
> @@ -744,11 +793,14 @@ static int rockchip_spi_probe(struct platform_device *pdev)
>   	master->bits_per_word_mask = SPI_BPW_MASK(16) | SPI_BPW_MASK(8);
>   
>   	master->set_cs = rockchip_spi_set_cs;
> +	master->setup = rockchip_spi_setup;
> +	master->cleanup = rockchip_spi_cleanup;
>   	master->prepare_message = rockchip_spi_prepare_message;
>   	master->unprepare_message = rockchip_spi_unprepare_message;
>   	master->transfer_one = rockchip_spi_transfer_one;
>   	master->max_transfer_size = rockchip_spi_max_transfer_size;
>   	master->handle_err = rockchip_spi_handle_err;
> +	master->flags = SPI_MASTER_GPIO_SS;
>   
>   	rs->dma_tx.ch = dma_request_chan(rs->dev, "tx");
>   	if (IS_ERR(rs->dma_tx.ch)) {
>
Geert Uytterhoeven June 12, 2017, 8:18 a.m. UTC | #2
On Mon, Jun 12, 2017 at 9:15 AM, Shawn Lin <shawn.lin@rock-chips.com> wrote:
> On 2017/6/12 14:14, Jeffy Chen wrote:
>>
>> Support using "cs-gpios" property to specify cs gpios.
>>
>> Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>

>> index 83da493..02171b2 100644
>> --- a/Documentation/devicetree/bindings/spi/spi-rockchip.txt
>> +++ b/Documentation/devicetree/bindings/spi/spi-rockchip.txt
>> @@ -17,6 +17,7 @@ Required Properties:
>>          region.
>>   - interrupts: The interrupt number to the cpu. The interrupt specifier
>> format
>>                 depends on the interrupt controller.
>> +- cs-gpios : Specifies the gpio pins to be used for chipselects.
>
> It's not a required property, otherwise how other boards work as your
> patch 2 only add this for rk3399-gru.

>> --- a/drivers/spi/spi-rockchip.c
>> +++ b/drivers/spi/spi-rockchip.c

>> @@ -297,6 +302,50 @@ static void rockchip_spi_set_cs(struct spi_device
>> *spi, bool enable)
>>         pm_runtime_put_sync(rs->dev);
>>   }
>>   +static int rockchip_spi_setup(struct spi_device *spi)
>> +{
>> +       int ret = 0;
>> +       unsigned long flags = (spi->mode & SPI_CS_HIGH) ?
>> +                             GPIOF_OUT_INIT_LOW : GPIOF_OUT_INIT_HIGH;
>> +       struct rockchip_spi_data *data = spi_get_ctldata(spi);
>> +
>> +       if (!gpio_is_valid(spi->cs_gpio))
>> +               return 0;

> return -EINVAL?

Isn't this check meant to fall back to hardware CS if no cs-gpios property
is present?

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds
Jeffy Chen June 12, 2017, 8:26 a.m. UTC | #3
Hi Shawn,

On 06/12/2017 03:15 PM, Shawn Lin wrote:
> Hi Jeffy,
>
> On 2017/6/12 14:14, Jeffy Chen wrote:
>> Support using "cs-gpios" property to specify cs gpios.
>>
>> Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
>> ---
>>
>>   .../devicetree/bindings/spi/spi-rockchip.txt       |  2 +
>>   drivers/spi/spi-rockchip.c                         | 52
>> ++++++++++++++++++++++
>>   2 files changed, 54 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/spi/spi-rockchip.txt
>> b/Documentation/devicetree/bindings/spi/spi-rockchip.txt
>> index 83da493..02171b2 100644
>> --- a/Documentation/devicetree/bindings/spi/spi-rockchip.txt
>> +++ b/Documentation/devicetree/bindings/spi/spi-rockchip.txt
>
> The changes for doc should be another patch, and...

but i saw others didn't separate them:
cf9e478 spi: sh-msiof: Add slave mode support
23e291c spi: rockchip: support "sleep" pin configuration


>
>> @@ -17,6 +17,7 @@ Required Properties:
>>          region.
>>   - interrupts: The interrupt number to the cpu. The interrupt
>> specifier format
>>                 depends on the interrupt controller.
>> +- cs-gpios : Specifies the gpio pins to be used for chipselects.
>
> It's not a required property, otherwise how other boards work as your
> patch 2 only add this for rk3399-gru.
oops, i will fix it.
>
>>   - clocks: Must contain an entry for each entry in clock-names.
>>   - clock-names: Shall be "spiclk" for the transfer-clock, and
>> "apb_pclk" for
>>                  the peripheral clock.
>> @@ -48,6 +49,7 @@ Example:
>>           #address-cells = <1>;
>>           #size-cells = <0>;
>>           interrupts = <GIC_SPI 44 IRQ_TYPE_LEVEL_HIGH>;
>> +        cs-gpios = <&gpio2 23 GPIO_ACTIVE_HIGH>;
>>           clocks = <&cru SCLK_SPI0>, <&cru PCLK_SPI0>;
>>           clock-names = "spiclk", "apb_pclk";
>>           pinctrl-0 = <&spi1_pins>;
>> diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c
>> index acf31f3..04694e1 100644
>> --- a/drivers/spi/spi-rockchip.c
>> +++ b/drivers/spi/spi-rockchip.c
>> @@ -15,6 +15,7 @@
>>   #include <linux/clk.h>
>>   #include <linux/dmaengine.h>
>> +#include <linux/gpio.h>
>>   #include <linux/module.h>
>>   #include <linux/of.h>
>>   #include <linux/pinctrl/consumer.h>
>> @@ -201,6 +202,10 @@ struct rockchip_spi {
>>       struct dma_slave_caps dma_caps;
>>   };
>> +struct rockchip_spi_data {
>> +    bool cs_gpio_requested;
>> +};
>> +
>
> Could you fold cs_gpio_requested into struct rockchip_spi?
>
>>   static inline void spi_enable_chip(struct rockchip_spi *rs, int enable)
>>   {
>>       writel_relaxed((enable ? 1 : 0), rs->regs + ROCKCHIP_SPI_SSIENR);
>> @@ -297,6 +302,50 @@ static void rockchip_spi_set_cs(struct spi_device
>> *spi, bool enable)
>>       pm_runtime_put_sync(rs->dev);
>>   }
>> +static int rockchip_spi_setup(struct spi_device *spi)
>> +{
>> +    int ret = 0;
>> +    unsigned long flags = (spi->mode & SPI_CS_HIGH) ?
>> +                  GPIOF_OUT_INIT_LOW : GPIOF_OUT_INIT_HIGH;
>> +    struct rockchip_spi_data *data = spi_get_ctldata(spi);
>> +
>> +    if (!gpio_is_valid(spi->cs_gpio))
>> +        return 0;
>
> return -EINVAL?
i think we can still support the original way, which means no "cs-gpios" 
and do nothing in setup.
>
>> +
>> +    if (!data) {
>> +        data = kzalloc(sizeof(*data), GFP_KERNEL);
>> +        if (!data)
>> +            return -ENOMEM;
>> +        spi_set_ctldata(spi, data);
>> +    }
>> +
>> +    if (!data->cs_gpio_requested) {
>> +        ret = gpio_request_one(spi->cs_gpio, flags,
>> +                       dev_name(&spi->dev));
>> +        if (!ret)
>> +            data->cs_gpio_requested = 1;
>> +    } else
>> +        ret = gpio_direction_output(spi->cs_gpio, flags);
>
> need brace around 'else' statement. Also I don't see data used
> elsewhere, so you need these code above.
ok.
and the cs_gpio_requested is to mark cs_gpio requested, because the 
setup func might be called multiple times, we only need to request gpio 
at the first time.
>
>> +
>> +    if (ret < 0)
>> +        dev_err(&spi->dev, "Failed to setup cs gpio(%d): %d\n",
>> +            spi->cs_gpio, ret);
>> +
>> +    return ret;
>> +}
>> +
>> +static void rockchip_spi_cleanup(struct spi_device *spi)
>> +{
>> +    struct rockchip_spi_data *data = spi_get_ctldata(spi);
>> +
>> +    if (data) {
>> +        if (data->cs_gpio_requested)
>> +            gpio_free(spi->cs_gpio);
>> +        kfree(data);
>> +        spi_set_ctldata(spi, NULL);
>> +    }
>> +}
>> +
>>   static int rockchip_spi_prepare_message(struct spi_master *master,
>>                       struct spi_message *msg)
>>   {
>> @@ -744,11 +793,14 @@ static int rockchip_spi_probe(struct
>> platform_device *pdev)
>>       master->bits_per_word_mask = SPI_BPW_MASK(16) | SPI_BPW_MASK(8);
>>       master->set_cs = rockchip_spi_set_cs;
>> +    master->setup = rockchip_spi_setup;
>> +    master->cleanup = rockchip_spi_cleanup;
>>       master->prepare_message = rockchip_spi_prepare_message;
>>       master->unprepare_message = rockchip_spi_unprepare_message;
>>       master->transfer_one = rockchip_spi_transfer_one;
>>       master->max_transfer_size = rockchip_spi_max_transfer_size;
>>       master->handle_err = rockchip_spi_handle_err;
>> +    master->flags = SPI_MASTER_GPIO_SS;
>>       rs->dma_tx.ch = dma_request_chan(rs->dev, "tx");
>>       if (IS_ERR(rs->dma_tx.ch)) {
>>
>
>
>
Jeffy Chen June 12, 2017, 8:33 a.m. UTC | #4
Hi Shawn,

On 06/12/2017 04:26 PM, jeffy wrote:
> Hi Shawn,
>
> On 06/12/2017 03:15 PM, Shawn Lin wrote:
>> Hi Jeffy,
>>
>> On 2017/6/12 14:14, Jeffy Chen wrote:
>>> Support using "cs-gpios" property to specify cs gpios.
>>>
>>> Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
>>> ---
>>>
>>>   .../devicetree/bindings/spi/spi-rockchip.txt       |  2 +
>>>   drivers/spi/spi-rockchip.c                         | 52
>>> ++++++++++++++++++++++
>>>   2 files changed, 54 insertions(+)
>>>
>>> diff --git a/Documentation/devicetree/bindings/spi/spi-rockchip.txt
>>> b/Documentation/devicetree/bindings/spi/spi-rockchip.txt
>>> index 83da493..02171b2 100644
>>> --- a/Documentation/devicetree/bindings/spi/spi-rockchip.txt
>>> +++ b/Documentation/devicetree/bindings/spi/spi-rockchip.txt
>>
>> The changes for doc should be another patch, and...
>
> but i saw others didn't separate them:
> cf9e478 spi: sh-msiof: Add slave mode support
> 23e291c spi: rockchip: support "sleep" pin configuration
>
>
>>
>>> @@ -17,6 +17,7 @@ Required Properties:
>>>          region.
>>>   - interrupts: The interrupt number to the cpu. The interrupt
>>> specifier format
>>>                 depends on the interrupt controller.
>>> +- cs-gpios : Specifies the gpio pins to be used for chipselects.
>>
>> It's not a required property, otherwise how other boards work as your
>> patch 2 only add this for rk3399-gru.
> oops, i will fix it.
>>
>>>   - clocks: Must contain an entry for each entry in clock-names.
>>>   - clock-names: Shall be "spiclk" for the transfer-clock, and
>>> "apb_pclk" for
>>>                  the peripheral clock.
>>> @@ -48,6 +49,7 @@ Example:
>>>           #address-cells = <1>;
>>>           #size-cells = <0>;
>>>           interrupts = <GIC_SPI 44 IRQ_TYPE_LEVEL_HIGH>;
>>> +        cs-gpios = <&gpio2 23 GPIO_ACTIVE_HIGH>;
>>>           clocks = <&cru SCLK_SPI0>, <&cru PCLK_SPI0>;
>>>           clock-names = "spiclk", "apb_pclk";
>>>           pinctrl-0 = <&spi1_pins>;
>>> diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c
>>> index acf31f3..04694e1 100644
>>> --- a/drivers/spi/spi-rockchip.c
>>> +++ b/drivers/spi/spi-rockchip.c
>>> @@ -15,6 +15,7 @@
>>>   #include <linux/clk.h>
>>>   #include <linux/dmaengine.h>
>>> +#include <linux/gpio.h>
>>>   #include <linux/module.h>
>>>   #include <linux/of.h>
>>>   #include <linux/pinctrl/consumer.h>
>>> @@ -201,6 +202,10 @@ struct rockchip_spi {
>>>       struct dma_slave_caps dma_caps;
>>>   };
>>> +struct rockchip_spi_data {
>>> +    bool cs_gpio_requested;
>>> +};
>>> +
>>
>> Could you fold cs_gpio_requested into struct rockchip_spi?
we might have multiple children with different cs_gpio, so i think we 
may need a separate data struct for them.
>>
>>>   static inline void spi_enable_chip(struct rockchip_spi *rs, int
>>> enable)
>>>   {
>>>       writel_relaxed((enable ? 1 : 0), rs->regs + ROCKCHIP_SPI_SSIENR);
>>> @@ -297,6 +302,50 @@ static void rockchip_spi_set_cs(struct spi_device
>>> *spi, bool enable)
>>>       pm_runtime_put_sync(rs->dev);
>>>   }
>>> +static int rockchip_spi_setup(struct spi_device *spi)
>>> +{
>>> +    int ret = 0;
>>> +    unsigned long flags = (spi->mode & SPI_CS_HIGH) ?
>>> +                  GPIOF_OUT_INIT_LOW : GPIOF_OUT_INIT_HIGH;
>>> +    struct rockchip_spi_data *data = spi_get_ctldata(spi);
>>> +
>>> +    if (!gpio_is_valid(spi->cs_gpio))
>>> +        return 0;
>>
>> return -EINVAL?
> i think we can still support the original way, which means no "cs-gpios"
> and do nothing in setup.
>>
>>> +
>>> +    if (!data) {
>>> +        data = kzalloc(sizeof(*data), GFP_KERNEL);
>>> +        if (!data)
>>> +            return -ENOMEM;
>>> +        spi_set_ctldata(spi, data);
>>> +    }
>>> +
>>> +    if (!data->cs_gpio_requested) {
>>> +        ret = gpio_request_one(spi->cs_gpio, flags,
>>> +                       dev_name(&spi->dev));
>>> +        if (!ret)
>>> +            data->cs_gpio_requested = 1;
>>> +    } else
>>> +        ret = gpio_direction_output(spi->cs_gpio, flags);
>>
>> need brace around 'else' statement. Also I don't see data used
>> elsewhere, so you need these code above.
> ok.
> and the cs_gpio_requested is to mark cs_gpio requested, because the
> setup func might be called multiple times, we only need to request gpio
> at the first time.
>>
>>> +
>>> +    if (ret < 0)
>>> +        dev_err(&spi->dev, "Failed to setup cs gpio(%d): %d\n",
>>> +            spi->cs_gpio, ret);
>>> +
>>> +    return ret;
>>> +}
>>> +
>>> +static void rockchip_spi_cleanup(struct spi_device *spi)
>>> +{
>>> +    struct rockchip_spi_data *data = spi_get_ctldata(spi);
>>> +
>>> +    if (data) {
>>> +        if (data->cs_gpio_requested)
>>> +            gpio_free(spi->cs_gpio);
>>> +        kfree(data);
>>> +        spi_set_ctldata(spi, NULL);
>>> +    }
>>> +}
>>> +
>>>   static int rockchip_spi_prepare_message(struct spi_master *master,
>>>                       struct spi_message *msg)
>>>   {
>>> @@ -744,11 +793,14 @@ static int rockchip_spi_probe(struct
>>> platform_device *pdev)
>>>       master->bits_per_word_mask = SPI_BPW_MASK(16) | SPI_BPW_MASK(8);
>>>       master->set_cs = rockchip_spi_set_cs;
>>> +    master->setup = rockchip_spi_setup;
>>> +    master->cleanup = rockchip_spi_cleanup;
>>>       master->prepare_message = rockchip_spi_prepare_message;
>>>       master->unprepare_message = rockchip_spi_unprepare_message;
>>>       master->transfer_one = rockchip_spi_transfer_one;
>>>       master->max_transfer_size = rockchip_spi_max_transfer_size;
>>>       master->handle_err = rockchip_spi_handle_err;
>>> +    master->flags = SPI_MASTER_GPIO_SS;
>>>       rs->dma_tx.ch = dma_request_chan(rs->dev, "tx");
>>>       if (IS_ERR(rs->dma_tx.ch)) {
>>>
>>
>>
>>
>
Heiko Stübner June 12, 2017, 8:36 a.m. UTC | #5
Am Montag, 12. Juni 2017, 16:26:07 CEST schrieb jeffy:
> Hi Shawn,
> 
> On 06/12/2017 03:15 PM, Shawn Lin wrote:
> > Hi Jeffy,
> > 
> > On 2017/6/12 14:14, Jeffy Chen wrote:
> >> Support using "cs-gpios" property to specify cs gpios.
> >> 
> >> Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
> >> ---
> >> 
> >>   .../devicetree/bindings/spi/spi-rockchip.txt       |  2 +
> >>   drivers/spi/spi-rockchip.c                         | 52
> >> 
> >> ++++++++++++++++++++++
> >> 
> >>   2 files changed, 54 insertions(+)
> >> 
> >> diff --git a/Documentation/devicetree/bindings/spi/spi-rockchip.txt
> >> b/Documentation/devicetree/bindings/spi/spi-rockchip.txt
> >> index 83da493..02171b2 100644
> >> --- a/Documentation/devicetree/bindings/spi/spi-rockchip.txt
> >> +++ b/Documentation/devicetree/bindings/spi/spi-rockchip.txt
> > 
> > The changes for doc should be another patch, and...
> 
> but i saw others didn't separate them:
> cf9e478 spi: sh-msiof: Add slave mode support
> 23e291c spi: rockchip: support "sleep" pin configuration

it sometimes falls through the cracks, but having dt-binding patches
separate is meant to make it easier on DT-Maintainers to find
patches they need to look at.


> >> +    if (!data->cs_gpio_requested) {
> >> +        ret = gpio_request_one(spi->cs_gpio, flags,
> >> +                       dev_name(&spi->dev));
> >> +        if (!ret)
> >> +            data->cs_gpio_requested = 1;
> >> +    } else
> >> +        ret = gpio_direction_output(spi->cs_gpio, flags);
> > 
> > need brace around 'else' statement. Also I don't see data used
> > elsewhere, so you need these code above.
> 
> ok.
> and the cs_gpio_requested is to mark cs_gpio requested, because the
> setup func might be called multiple times, we only need to request gpio
> at the first time.

Aren't the gpiod* functions meant to be used for new things?
Also you might actually do a bit of error handling there, especially 
EPROBE_DEFER.


Heiko
Jeffy Chen June 12, 2017, 8:48 a.m. UTC | #6
Hi Geert,

On 06/12/2017 04:18 PM, Geert Uytterhoeven wrote:
> On Mon, Jun 12, 2017 at 9:15 AM, Shawn Lin <shawn.lin@rock-chips.com> wrote:
>> On 2017/6/12 14:14, Jeffy Chen wrote:
>>>
>>> Support using "cs-gpios" property to specify cs gpios.
>>>
>>> Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
>
>>> index 83da493..02171b2 100644
>>> --- a/Documentation/devicetree/bindings/spi/spi-rockchip.txt
>>> +++ b/Documentation/devicetree/bindings/spi/spi-rockchip.txt
>>> @@ -17,6 +17,7 @@ Required Properties:
>>>           region.
>>>    - interrupts: The interrupt number to the cpu. The interrupt specifier
>>> format
>>>                  depends on the interrupt controller.
>>> +- cs-gpios : Specifies the gpio pins to be used for chipselects.
>>
>> It's not a required property, otherwise how other boards work as your
>> patch 2 only add this for rk3399-gru.
>
>>> --- a/drivers/spi/spi-rockchip.c
>>> +++ b/drivers/spi/spi-rockchip.c
>
>>> @@ -297,6 +302,50 @@ static void rockchip_spi_set_cs(struct spi_device
>>> *spi, bool enable)
>>>          pm_runtime_put_sync(rs->dev);
>>>    }
>>>    +static int rockchip_spi_setup(struct spi_device *spi)
>>> +{
>>> +       int ret = 0;
>>> +       unsigned long flags = (spi->mode & SPI_CS_HIGH) ?
>>> +                             GPIOF_OUT_INIT_LOW : GPIOF_OUT_INIT_HIGH;
>>> +       struct rockchip_spi_data *data = spi_get_ctldata(spi);
>>> +
>>> +       if (!gpio_is_valid(spi->cs_gpio))
>>> +               return 0;
>
>> return -EINVAL?
>
> Isn't this check meant to fall back to hardware CS if no cs-gpios property
> is present?

Thanks for your comment, and yes it is. I'll add a comment in the code 
to explain it :)
>
> Gr{oetje,eeting}s,
>
>                          Geert
>
> --
> Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
>
> In personal conversations with technical people, I call myself a hacker. But
> when I'm talking to journalists I just say "programmer" or something like that.
>                                  -- Linus Torvalds
>
>
>
Jeffy Chen June 12, 2017, 9:12 a.m. UTC | #7
Hi Heiko,

thanx for your comments.

On 06/12/2017 04:36 PM, Heiko Stübner wrote:
> Am Montag, 12. Juni 2017, 16:26:07 CEST schrieb jeffy:
>> Hi Shawn,
>>
>> On 06/12/2017 03:15 PM, Shawn Lin wrote:
>>> Hi Jeffy,
>>>
>>> On 2017/6/12 14:14, Jeffy Chen wrote:
>>>> Support using "cs-gpios" property to specify cs gpios.
>>>>
>>>> Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
>>>> ---
>>>>
>>>>    .../devicetree/bindings/spi/spi-rockchip.txt       |  2 +
>>>>    drivers/spi/spi-rockchip.c                         | 52
>>>>
>>>> ++++++++++++++++++++++
>>>>
>>>>    2 files changed, 54 insertions(+)
>>>>
>>>> diff --git a/Documentation/devicetree/bindings/spi/spi-rockchip.txt
>>>> b/Documentation/devicetree/bindings/spi/spi-rockchip.txt
>>>> index 83da493..02171b2 100644
>>>> --- a/Documentation/devicetree/bindings/spi/spi-rockchip.txt
>>>> +++ b/Documentation/devicetree/bindings/spi/spi-rockchip.txt
>>>
>>> The changes for doc should be another patch, and...
>>
>> but i saw others didn't separate them:
>> cf9e478 spi: sh-msiof: Add slave mode support
>> 23e291c spi: rockchip: support "sleep" pin configuration
>
> it sometimes falls through the cracks, but having dt-binding patches
> separate is meant to make it easier on DT-Maintainers to find
> patches they need to look at.
ok, will do.
>
>
>>>> +    if (!data->cs_gpio_requested) {
>>>> +        ret = gpio_request_one(spi->cs_gpio, flags,
>>>> +                       dev_name(&spi->dev));
>>>> +        if (!ret)
>>>> +            data->cs_gpio_requested = 1;
>>>> +    } else
>>>> +        ret = gpio_direction_output(spi->cs_gpio, flags);
>>>
>>> need brace around 'else' statement. Also I don't see data used
>>> elsewhere, so you need these code above.
>>
>> ok.
>> and the cs_gpio_requested is to mark cs_gpio requested, because the
>> setup func might be called multiple times, we only need to request gpio
>> at the first time.
>
> Aren't the gpiod* functions meant to be used for new things?
> Also you might actually do a bit of error handling there, especially
> EPROBE_DEFER.
so you are suggesting to use gpiod* functions here to replace gpio_* 
functions right?
>
>
> Heiko
>
>
>
Heiko Stübner June 12, 2017, 9:23 a.m. UTC | #8
Am Montag, 12. Juni 2017, 17:12:24 CEST schrieb jeffy:
> Hi Heiko,
> 
> thanx for your comments.
> 
> On 06/12/2017 04:36 PM, Heiko Stübner wrote:
> > Am Montag, 12. Juni 2017, 16:26:07 CEST schrieb jeffy:
> >> Hi Shawn,
> >> 
> >> On 06/12/2017 03:15 PM, Shawn Lin wrote:
> >>> Hi Jeffy,
> >>> 
> >>> On 2017/6/12 14:14, Jeffy Chen wrote:
> >>>> Support using "cs-gpios" property to specify cs gpios.
> >>>> 
> >>>> Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
> >>>> ---
> >>>> 
> >>>>    .../devicetree/bindings/spi/spi-rockchip.txt       |  2 +
> >>>>    drivers/spi/spi-rockchip.c                         | 52
> >>>> 
> >>>> ++++++++++++++++++++++
> >>>> 
> >>>>    2 files changed, 54 insertions(+)
> >>>> 
> >>>> diff --git a/Documentation/devicetree/bindings/spi/spi-rockchip.txt
> >>>> b/Documentation/devicetree/bindings/spi/spi-rockchip.txt
> >>>> index 83da493..02171b2 100644
> >>>> --- a/Documentation/devicetree/bindings/spi/spi-rockchip.txt
> >>>> +++ b/Documentation/devicetree/bindings/spi/spi-rockchip.txt
> >>> 
> >>> The changes for doc should be another patch, and...
> >> 
> >> but i saw others didn't separate them:
> >> cf9e478 spi: sh-msiof: Add slave mode support
> >> 23e291c spi: rockchip: support "sleep" pin configuration
> > 
> > it sometimes falls through the cracks, but having dt-binding patches
> > separate is meant to make it easier on DT-Maintainers to find
> > patches they need to look at.
> 
> ok, will do.
> 
> >>>> +    if (!data->cs_gpio_requested) {
> >>>> +        ret = gpio_request_one(spi->cs_gpio, flags,
> >>>> +                       dev_name(&spi->dev));
> >>>> +        if (!ret)
> >>>> +            data->cs_gpio_requested = 1;
> >>>> +    } else
> >>>> +        ret = gpio_direction_output(spi->cs_gpio, flags);
> >>> 
> >>> need brace around 'else' statement. Also I don't see data used
> >>> elsewhere, so you need these code above.
> >> 
> >> ok.
> >> and the cs_gpio_requested is to mark cs_gpio requested, because the
> >> setup func might be called multiple times, we only need to request gpio
> >> at the first time.
> > 
> > Aren't the gpiod* functions meant to be used for new things?
> > Also you might actually do a bit of error handling there, especially
> > EPROBE_DEFER.
> 
> so you are suggesting to use gpiod* functions here to replace gpio_*
> functions right?

correct. And handle errors that may get returned, especially EPROBE_DEFER,
but also other errors may indicate that your spi won't function as expected.


Heiko
Mark Brown June 12, 2017, 4:38 p.m. UTC | #9
On Mon, Jun 12, 2017 at 10:18:06AM +0200, Geert Uytterhoeven wrote:
> On Mon, Jun 12, 2017 at 9:15 AM, Shawn Lin <shawn.lin@rock-chips.com> wrote:
> > On 2017/6/12 14:14, Jeffy Chen wrote:

> >>   +static int rockchip_spi_setup(struct spi_device *spi)
> >> +{
> >> +       int ret = 0;
> >> +       unsigned long flags = (spi->mode & SPI_CS_HIGH) ?
> >> +                             GPIOF_OUT_INIT_LOW : GPIOF_OUT_INIT_HIGH;
> >> +       struct rockchip_spi_data *data = spi_get_ctldata(spi);
> >> +
> >> +       if (!gpio_is_valid(spi->cs_gpio))
> >> +               return 0;

> > return -EINVAL?

> Isn't this check meant to fall back to hardware CS if no cs-gpios property
> is present?

I'd expect it to, otherwise the cs-gpios property is actualy mandatory.
diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/spi/spi-rockchip.txt b/Documentation/devicetree/bindings/spi/spi-rockchip.txt
index 83da493..02171b2 100644
--- a/Documentation/devicetree/bindings/spi/spi-rockchip.txt
+++ b/Documentation/devicetree/bindings/spi/spi-rockchip.txt
@@ -17,6 +17,7 @@  Required Properties:
        region.
 - interrupts: The interrupt number to the cpu. The interrupt specifier format
               depends on the interrupt controller.
+- cs-gpios : Specifies the gpio pins to be used for chipselects.
 - clocks: Must contain an entry for each entry in clock-names.
 - clock-names: Shall be "spiclk" for the transfer-clock, and "apb_pclk" for
 			   the peripheral clock.
@@ -48,6 +49,7 @@  Example:
 		#address-cells = <1>;
 		#size-cells = <0>;
 		interrupts = <GIC_SPI 44 IRQ_TYPE_LEVEL_HIGH>;
+		cs-gpios = <&gpio2 23 GPIO_ACTIVE_HIGH>;
 		clocks = <&cru SCLK_SPI0>, <&cru PCLK_SPI0>;
 		clock-names = "spiclk", "apb_pclk";
 		pinctrl-0 = <&spi1_pins>;
diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c
index acf31f3..04694e1 100644
--- a/drivers/spi/spi-rockchip.c
+++ b/drivers/spi/spi-rockchip.c
@@ -15,6 +15,7 @@ 
 
 #include <linux/clk.h>
 #include <linux/dmaengine.h>
+#include <linux/gpio.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/pinctrl/consumer.h>
@@ -201,6 +202,10 @@  struct rockchip_spi {
 	struct dma_slave_caps dma_caps;
 };
 
+struct rockchip_spi_data {
+	bool cs_gpio_requested;
+};
+
 static inline void spi_enable_chip(struct rockchip_spi *rs, int enable)
 {
 	writel_relaxed((enable ? 1 : 0), rs->regs + ROCKCHIP_SPI_SSIENR);
@@ -297,6 +302,50 @@  static void rockchip_spi_set_cs(struct spi_device *spi, bool enable)
 	pm_runtime_put_sync(rs->dev);
 }
 
+static int rockchip_spi_setup(struct spi_device *spi)
+{
+	int ret = 0;
+	unsigned long flags = (spi->mode & SPI_CS_HIGH) ?
+			      GPIOF_OUT_INIT_LOW : GPIOF_OUT_INIT_HIGH;
+	struct rockchip_spi_data *data = spi_get_ctldata(spi);
+
+	if (!gpio_is_valid(spi->cs_gpio))
+		return 0;
+
+	if (!data) {
+		data = kzalloc(sizeof(*data), GFP_KERNEL);
+		if (!data)
+			return -ENOMEM;
+		spi_set_ctldata(spi, data);
+	}
+
+	if (!data->cs_gpio_requested) {
+		ret = gpio_request_one(spi->cs_gpio, flags,
+				       dev_name(&spi->dev));
+		if (!ret)
+			data->cs_gpio_requested = 1;
+	} else
+		ret = gpio_direction_output(spi->cs_gpio, flags);
+
+	if (ret < 0)
+		dev_err(&spi->dev, "Failed to setup cs gpio(%d): %d\n",
+			spi->cs_gpio, ret);
+
+	return ret;
+}
+
+static void rockchip_spi_cleanup(struct spi_device *spi)
+{
+	struct rockchip_spi_data *data = spi_get_ctldata(spi);
+
+	if (data) {
+		if (data->cs_gpio_requested)
+			gpio_free(spi->cs_gpio);
+		kfree(data);
+		spi_set_ctldata(spi, NULL);
+	}
+}
+
 static int rockchip_spi_prepare_message(struct spi_master *master,
 					struct spi_message *msg)
 {
@@ -744,11 +793,14 @@  static int rockchip_spi_probe(struct platform_device *pdev)
 	master->bits_per_word_mask = SPI_BPW_MASK(16) | SPI_BPW_MASK(8);
 
 	master->set_cs = rockchip_spi_set_cs;
+	master->setup = rockchip_spi_setup;
+	master->cleanup = rockchip_spi_cleanup;
 	master->prepare_message = rockchip_spi_prepare_message;
 	master->unprepare_message = rockchip_spi_unprepare_message;
 	master->transfer_one = rockchip_spi_transfer_one;
 	master->max_transfer_size = rockchip_spi_max_transfer_size;
 	master->handle_err = rockchip_spi_handle_err;
+	master->flags = SPI_MASTER_GPIO_SS;
 
 	rs->dma_tx.ch = dma_request_chan(rs->dev, "tx");
 	if (IS_ERR(rs->dma_tx.ch)) {