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

Nicolas Ferre
2014-09-12T07:53:01Z

On 11/09/2014 19:52, Alexandre Belloni :
> From: Boris BREZILLON <boris.brezillon@free-electrons.com>
>
> Signed-off-by: Boris BREZILLON <boris.brezillon@free-electrons.com>
> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>

You may need to add Josh Wu to the list because he is the "de-facto"
Maintainer of this driver.

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@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 = {
>

--
Nicolas Ferre