Subject: [PATCHv2] mtd: nand: atmel_nand: retrieve NFC clock

From: [email-masked] (Josh Wu)
Date: Fri, 12 Sep 2014 16:48:34 +0800

Hi, Nicolas

On 9/12/2014 3:52 PM, Nicolas Ferre wrote:
> On 11/09/2014 19:52, Alexandre Belloni :
>> From: Boris BREZILLON <[email-masked]>
>>
>> Signed-off-by: Boris BREZILLON <[email-masked]>
>> Signed-off-by: Alexandre Belloni <[email-masked]>
> You may need to add Josh Wu to the list because he is the "de-facto"
> Maintainer of this driver.

Thanks for the email.
I almost miss it.

Best Regards,
Josh Wu
>
> Bye,
>
>> ---
>>
>> Changes in v2:
>>   - reworked the error path to really make the clock optional
>>   - Documented the new optional property
>>
>>   .../devicetree/bindings/mtd/atmel-nand.txt         |  1 +
>>   drivers/mtd/nand/atmel_nand.c                      | 25 ++++++++++++++++++++++
>>   2 files changed, 26 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/mtd/atmel-nand.txt b/Documentation/devicetree/bindings/mtd/atmel-nand.txt
>> index c4728839d0c1..f71e2ebab15b 100644
>> --- a/Documentation/devicetree/bindings/mtd/atmel-nand.txt
>> +++ b/Documentation/devicetree/bindings/mtd/atmel-nand.txt
>> @@ -38,6 +38,7 @@ Optional properties:
>>               if don't want to use it.
>>     - Optional properties:
>>       - atmel,write-by-sram: boolean to enable NFC write by sram.
>> +    - clocks: phandle to the peripheral clock if it exists
>>   
>>   Examples:
>>   nand0: nand at 40000000,0 {
>> diff --git a/drivers/mtd/nand/atmel_nand.c b/drivers/mtd/nand/atmel_nand.c
>> index 9c5f717bda54..69e0eb1ace54 100644
>> --- a/drivers/mtd/nand/atmel_nand.c
>> +++ b/drivers/mtd/nand/atmel_nand.c
>> @@ -27,6 +27,7 @@
>>    *
>>    */
>>   
>> +#include <linux/clk.h>
>>   #include <linux/dma-mapping.h>
>>   #include <linux/slab.h>
>>   #include <linux/module.h>
>> @@ -96,6 +97,8 @@ struct atmel_nfc {
>>   	bool			use_nfc_sram;
>>   	bool			write_by_sram;
>>   
>> +	struct clk		*clk;
>> +
>>   	bool			is_initialized;
>>   	struct completion	comp_ready;
>>   	struct completion	comp_cmd_done;
>> @@ -2248,6 +2251,7 @@ static int atmel_nand_nfc_probe(struct platform_device *pdev)
>>   {
>>   	struct atmel_nfc *nfc = &nand_nfc;
>>   	struct resource *nfc_cmd_regs, *nfc_hsmc_regs, *nfc_sram;
>> +	int ret;
>>   
>>   	nfc_cmd_regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>>   	nfc->base_cmd_regs = devm_ioremap_resource(&pdev->dev, nfc_cmd_regs);
>> @@ -2281,6 +2285,26 @@ static int atmel_nand_nfc_probe(struct platform_device *pdev)
>>   
>>   	nfc->is_initialized = true;
>>   	dev_info(&pdev->dev, "NFC is probed.\n");
>> +
>> +	nfc->clk = devm_clk_get(&pdev->dev, NULL);
>> +	if (!IS_ERR(nfc->clk)) {
>> +		ret = clk_prepare_enable(nfc->clk);
>> +		if (ret)
>> +			return ret;
>> +	} else {
>> +		dev_warn(&pdev->dev, "NFC clock is missing");
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int atmel_nand_nfc_remove(struct platform_device *pdev)
>> +{
>> +	struct atmel_nfc *nfc = &nand_nfc;
>> +
>> +	if (!IS_ERR(nfc->clk))
>> +		clk_disable_unprepare(nfc->clk);
>> +
>>   	return 0;
>>   }
>>   
>> @@ -2297,6 +2321,7 @@ static struct platform_driver atmel_nand_nfc_driver = {
>>   		.of_match_table = of_match_ptr(atmel_nand_nfc_match),
>>   	},
>>   	.probe = atmel_nand_nfc_probe,
>> +	.remove = atmel_nand_nfc_remove,
>>   };
>>   
>>   static struct platform_driver atmel_nand_driver = {
>>
>