Re: [FOR 3.4 PATCH 5/6] atmel/nand: add DT support

[Grant Likely <grant.likely-s3s/WqlpOiPyB63q8FvJNQ@public.gmane.org>]

On Sat, Jan 28, 2012 at 06:10:43AM +0100, Jean-Christophe PLAGNIOL-VILLARD wrote:
> use a local copy of board informatin and fill with DT data
> 
> Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj-sclMFOaUSTBWk0Htik3J/w@public.gmane.org>
> Cc: Nicolas Ferre <nicolas.ferre-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org>
> Cc: devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org
> Cc: linux-mtd-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org

Nitpicks below, but otherwise:

Acked-by: Grant Likely <grant.likely-s3s/WqlpOiPyB63q8FvJNQ@public.gmane.org>

> ---
>  .../devicetree/bindings/mtd/atmel-nand.txt         |   41 ++++++++
>  drivers/mtd/nand/atmel_nand.c                      |  107 ++++++++++++++++----
>  2 files changed, 130 insertions(+), 18 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/mtd/atmel-nand.txt
> 
> diff --git a/Documentation/devicetree/bindings/mtd/atmel-nand.txt b/Documentation/devicetree/bindings/mtd/atmel-nand.txt
> new file mode 100644
> index 0000000..a910ab9
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mtd/atmel-nand.txt
> @@ -0,0 +1,41 @@
> +Atmel NAND flash
> +
> +Required properties:
> +- compatible : "atmel,at91rm9200-nand".
> +- reg : should specify localbus address and size used for the chip,
> +	and if availlable the ECC.
> +- atmel,nand-addr-offset : offset for the address latch.
> +- atmel,nand-cmd-offset : offset for the command latch.
> +- #address-cells, #size-cells : Must be present if the device has sub-nodes
> +  representing partitions.
> +
> +- gpios : specifies the gpio pins to control the NAND device. detect is an
> +  optional gpio and may be set to 0 if not present.
> +
> +Optional properties:
> +- nand-ecc-mode : String, operation mode of the NAND ecc mode, soft by default.
> +  Supported values are: "none", "soft", "hw", "hw_syndrome", "hw_oob_first",
> +  "soft_bch".
> +- nand-bus-width : 8 or 16 bus width if not present 8
> +- nand-on-flash-bbt: boolean to enable on flash bbt option if not present false
> +
> +Examples:
> +nand0: nand@40000000,0 {
> +	compatible = "atmel,at91rm9200-nand";
> +	#address-cells = <1>;
> +	#size-cells = <1>;
> +	reg = <0x40000000 0x10000000
> +	       0xffffe800 0x200
> +	      >;
> +	atmel,nand-addr-offset = <21>;
> +	atmel,nand-cmd-offset = <22>;
> +	nand-on-flash-bbt = <1>;
> +	nand-ecc-mode = "soft";
> +	gpios = <&pioC 13 0
> +		 &pioC 14 0
> +		 0
> +		>;
> +	partition@0 {
> +		...
> +	};
> +};
> diff --git a/drivers/mtd/nand/atmel_nand.c b/drivers/mtd/nand/atmel_nand.c
> index d3bde9b..ea7643a 100644
> --- a/drivers/mtd/nand/atmel_nand.c
> +++ b/drivers/mtd/nand/atmel_nand.c
> @@ -27,6 +27,10 @@
>  #include <linux/module.h>
>  #include <linux/moduleparam.h>
>  #include <linux/platform_device.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
> +#include <linux/of_gpio.h>
> +#include <linux/of_mtd.h>
>  #include <linux/mtd/mtd.h>
>  #include <linux/mtd/nand.h>
>  #include <linux/mtd/partitions.h>
> @@ -83,7 +87,7 @@ struct atmel_nand_host {
>  	struct mtd_info		mtd;
>  	void __iomem		*io_base;
>  	dma_addr_t		io_phys;
> -	struct atmel_nand_data	*board;
> +	struct atmel_nand_data	board;
>  	struct device		*dev;
>  	void __iomem		*ecc;
>  
> @@ -101,8 +105,8 @@ static int cpu_has_dma(void)
>   */
>  static void atmel_nand_enable(struct atmel_nand_host *host)
>  {
> -	if (gpio_is_valid(host->board->enable_pin))
> -		gpio_set_value(host->board->enable_pin, 0);
> +	if (gpio_is_valid(host->board.enable_pin))
> +		gpio_set_value(host->board.enable_pin, 0);
>  }
>  
>  /*
> @@ -110,8 +114,8 @@ static void atmel_nand_enable(struct atmel_nand_host *host)
>   */
>  static void atmel_nand_disable(struct atmel_nand_host *host)
>  {
> -	if (gpio_is_valid(host->board->enable_pin))
> -		gpio_set_value(host->board->enable_pin, 1);
> +	if (gpio_is_valid(host->board.enable_pin))
> +		gpio_set_value(host->board.enable_pin, 1);
>  }
>  
>  /*
> @@ -132,9 +136,9 @@ static void atmel_nand_cmd_ctrl(struct mtd_info *mtd, int cmd, unsigned int ctrl
>  		return;
>  
>  	if (ctrl & NAND_CLE)
> -		writeb(cmd, host->io_base + (1 << host->board->cle));
> +		writeb(cmd, host->io_base + (1 << host->board.cle));
>  	else
> -		writeb(cmd, host->io_base + (1 << host->board->ale));
> +		writeb(cmd, host->io_base + (1 << host->board.ale));
>  }
>  
>  /*
> @@ -145,8 +149,8 @@ static int atmel_nand_device_ready(struct mtd_info *mtd)
>  	struct nand_chip *nand_chip = mtd->priv;
>  	struct atmel_nand_host *host = nand_chip->priv;
>  
> -	return gpio_get_value(host->board->rdy_pin) ^
> -                !!host->board->rdy_pin_active_low;
> +	return gpio_get_value(host->board.rdy_pin) ^
> +                !!host->board.rdy_pin_active_low;
>  }
>  
>  static void dma_complete_func(void *completion)
> @@ -432,6 +436,54 @@ static void atmel_nand_hwctl(struct mtd_info *mtd, int mode)
>  	}
>  }
>  
> +static int __devinit atmel_of_init_port(struct atmel_nand_host *host,
> +					 struct device_node *np)
> +{
> +	u32 val;
> +	int ecc_mode;
> +	struct atmel_nand_data *board = &host->board;
> +	enum of_gpio_flags flags;
> +
> +	if (of_property_read_u32(np, "atmel,nand-addr-offset", &val) == 0) {
> +		if (val >= 32) {
> +			dev_err(host->dev, "invalid addr-offset %u\n", val);
> +			return -EINVAL;
> +		}
> +		board->ale = val;
> +	}
> +
> +	if (of_property_read_u32(np, "atmel,nand-cmd-offset", &val) == 0) {
> +		if (val >= 32) {
> +			dev_err(host->dev, "invalid cmd-offset %u\n", val);
> +			return -EINVAL;
> +		}
> +		board->cle = val;
> +	}
> +
> +	ecc_mode = of_get_nand_ecc_mode(np);
> +
> +	if (ecc_mode < 0)
> +		board->ecc_mode = NAND_ECC_SOFT;
> +	else
> +		board->ecc_mode = ecc_mode;

Nit: board->ecc_mode = ecc_mode < 0 ? NAND_ECC_SOFT : ecc_mode;

> +
> +	board->on_flash_bbt = of_get_nand_on_flash_bbt(np);
> +
> +	if (of_get_nand_bus_width(np) == 16)
> +		board->bus_width_16 = 1;
> +
> +	board->rdy_pin = of_get_gpio_flags(np, 0, &flags);
> +	if (flags == OF_GPIO_ACTIVE_LOW)
> +		board->rdy_pin_active_low = 1;
> +	else
> +		board->rdy_pin_active_low = 0;

Nit: board->rdy_pin_active_low = (flags == OF_GPIO_ACTIVE_LOW);

Just a bit more compact that way.

> +
> +	board->enable_pin = of_get_gpio(np, 1);
> +	board->det_pin = of_get_gpio(np, 2);
> +
> +	return 0;
> +}
> +
>  /*
>   * Probe for the NAND device.
>   */
> @@ -442,6 +494,7 @@ static int __init atmel_nand_probe(struct platform_device *pdev)
>  	struct nand_chip *nand_chip;
>  	struct resource *regs;
>  	struct resource *mem;
> +	struct mtd_part_parser_data ppdata = {};
>  	int res;
>  
>  	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> @@ -468,8 +521,15 @@ static int __init atmel_nand_probe(struct platform_device *pdev)
>  
>  	mtd = &host->mtd;
>  	nand_chip = &host->nand_chip;
> -	host->board = pdev->dev.platform_data;
>  	host->dev = &pdev->dev;
> +	if (pdev->dev.of_node) {
> +		res = atmel_of_init_port(host, pdev->dev.of_node);
> +		if (res)
> +			goto err_nand_ioremap;
> +	} else {
> +		memcpy(&host->board, pdev->dev.platform_data,
> +		       sizeof(struct atmel_nand_data));
> +	}
>  
>  	nand_chip->priv = host;		/* link the private data structures */
>  	mtd->priv = nand_chip;
> @@ -480,10 +540,10 @@ static int __init atmel_nand_probe(struct platform_device *pdev)
>  	nand_chip->IO_ADDR_W = host->io_base;
>  	nand_chip->cmd_ctrl = atmel_nand_cmd_ctrl;
>  
> -	if (gpio_is_valid(host->board->rdy_pin))
> +	if (gpio_is_valid(host->board.rdy_pin))
>  		nand_chip->dev_ready = atmel_nand_device_ready;
>  
> -	nand_chip->ecc.mode = host->board->ecc_mode;
> +	nand_chip->ecc.mode = host->board.ecc_mode;
>  
>  	regs = platform_get_resource(pdev, IORESOURCE_MEM, 1);
>  	if (!regs && nand_chip->ecc.mode == NAND_ECC_HW) {
> @@ -508,7 +568,7 @@ static int __init atmel_nand_probe(struct platform_device *pdev)
>  
>  	nand_chip->chip_delay = 20;		/* 20us command delay time */
>  
> -	if (host->board->bus_width_16)	/* 16-bit bus width */
> +	if (host->board.bus_width_16)	/* 16-bit bus width */
>  		nand_chip->options |= NAND_BUSWIDTH_16;
>  
>  	nand_chip->read_buf = atmel_read_buf;
> @@ -517,15 +577,15 @@ static int __init atmel_nand_probe(struct platform_device *pdev)
>  	platform_set_drvdata(pdev, host);
>  	atmel_nand_enable(host);
>  
> -	if (gpio_is_valid(host->board->det_pin)) {
> -		if (gpio_get_value(host->board->det_pin)) {
> +	if (gpio_is_valid(host->board.det_pin)) {
> +		if (gpio_get_value(host->board.det_pin)) {
>  			printk(KERN_INFO "No SmartMedia card inserted.\n");
>  			res = -ENXIO;
>  			goto err_no_card;
>  		}
>  	}
>  
> -	if (host->board->on_flash_bbt || on_flash_bbt) {
> +	if (host->board.on_flash_bbt || on_flash_bbt) {
>  		printk(KERN_INFO "atmel_nand: Use On Flash BBT\n");
>  		nand_chip->bbt_options |= NAND_BBT_USE_FLASH;
>  	}
> @@ -600,8 +660,9 @@ static int __init atmel_nand_probe(struct platform_device *pdev)
>  	}
>  
>  	mtd->name = "atmel_nand";
> -	res = mtd_device_parse_register(mtd, NULL, 0,
> -			host->board->parts, host->board->num_parts);
> +	ppdata.of_node = pdev->dev.of_node;
> +	res = mtd_device_parse_register(mtd, NULL, &ppdata,
> +			host->board.parts, host->board.num_parts);
>  	if (!res)
>  		return res;
>  
> @@ -645,11 +706,21 @@ static int __exit atmel_nand_remove(struct platform_device *pdev)
>  	return 0;
>  }
>  
> +#if defined(CONFIG_OF)
> +static const struct of_device_id atmel_nand_dt_ids[] = {
> +	{ .compatible = "atmel,at91rm9200-nand" },
> +	{ /* sentinel */ }
> +};
> +
> +MODULE_DEVICE_TABLE(of, atmel_nand_dt_ids);
> +#endif
> +
>  static struct platform_driver atmel_nand_driver = {
>  	.remove		= __exit_p(atmel_nand_remove),
>  	.driver		= {
>  		.name	= "atmel_nand",
>  		.owner	= THIS_MODULE,
> +		.of_match_table	= of_match_ptr(atmel_nand_dt_ids),
>  	},
>  };
>  
> -- 
> 1.7.7
> 
> 
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