Re: [PATCH 11/46] ARM: pxa: cmx270: use platform device for nand

Miquel Raynal
2019-10-19T09:44:45Z

Hi Arnd,

Arnd Bergmann <arnd@arndb.de> wrote on Fri, 18 Oct 2019 17:41:26 +0200:

> The driver traditionally hardcodes the MMIO register address and
> the GPIO numbers from data defined in platform header files.
>
> To make it indepdendent of that, use a memory resource for the
> registers, and a gpio lookup table to replace the gpio numbers.

Looks good to me besides the typo s/indepdendent/independent/.

Acked-by: Miquel Raynal <miquel.raynal@bootlin.com>

>
> Cc: Miquel Raynal <miquel.raynal@bootlin.com>
> Cc: Richard Weinberger <richard@nod.at>
> Cc: David Woodhouse <dwmw2@infradead.org>
> Cc: Brian Norris <computersforpeace@gmail.com>
> Cc: Marek Vasut <marek.vasut@gmail.com>
> Cc: Vignesh Raghavendra <vigneshr@ti.com>
> Cc: linux-mtd@lists.infradead.org
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
> arch/arm/mach-pxa/cm-x270.c | 25 +++++++++
> drivers/mtd/nand/raw/cmx270_nand.c | 88 +++++++++++-------------------
> 2 files changed, 56 insertions(+), 57 deletions(-)
>
> diff --git a/arch/arm/mach-pxa/cm-x270.c b/arch/arm/mach-pxa/cm-x270.c
> index 9baad11314f2..6d80400d8887 100644
> --- a/arch/arm/mach-pxa/cm-x270.c
> +++ b/arch/arm/mach-pxa/cm-x270.c
> @@ -40,6 +40,10 @@
> #define GPIO19_WLAN_STRAP (19)
> #define GPIO102_WLAN_RST (102)
>
> +/* NAND GPIOS */
> +#define GPIO_NAND_CS (11)
> +#define GPIO_NAND_RB (89)
> +
> static unsigned long cmx270_pin_config[] = {
> /* AC'97 */
> GPIO28_AC97_BITCLK,
> @@ -403,6 +407,26 @@ static void __init cmx270_init_spi(void)
> static inline void cmx270_init_spi(void) {}
> #endif
>
> +static struct gpiod_lookup_table cmx270_nand_gpio_table = {
> + .dev_id = "cmx270-nand",
> + .table = {
> + GPIO_LOOKUP("gpio-pxa", GPIO_NAND_CS, "cs", GPIO_ACTIVE_HIGH),
> + GPIO_LOOKUP("gpio-pxa", GPIO_NAND_RB, "rb", GPIO_ACTIVE_HIGH),
> + { },
> + },
> +};
> +
> +static struct resource cmx270_nand_resources[] __initdata = {
> + DEFINE_RES_MEM(PXA_CS1_PHYS, 12),
> +};
> +
> +static void __init cmx270_init_nand(void)
> +{
> + platform_device_register_simple("cmx270-nand", -1,
> + cmx270_nand_resources, 1);
> + gpiod_add_lookup_table(&cmx270_nand_gpio_table);
> +}
> +
> void __init cmx270_init(void)
> {
> pxa2xx_mfp_config(ARRAY_AND_SIZE(cmx270_pin_config));
> @@ -416,4 +440,5 @@ void __init cmx270_init(void)
> cmx270_init_ohci();
> cmx270_init_2700G();
> cmx270_init_spi();
> + cmx270_init_nand();
> }
> diff --git a/drivers/mtd/nand/raw/cmx270_nand.c b/drivers/mtd/nand/raw/cmx270_nand.c
> index 7af3d0bdcdb8..31cb20858c46 100644
> --- a/drivers/mtd/nand/raw/cmx270_nand.c
> +++ b/drivers/mtd/nand/raw/cmx270_nand.c
> @@ -15,18 +15,17 @@
> #include <linux/mtd/rawnand.h>
> #include <linux/mtd/partitions.h>
> #include <linux/slab.h>
> -#include <linux/gpio.h>
> +#include <linux/gpio/consumer.h>
> #include <linux/module.h>
> #include <linux/soc/pxa/cpu.h>
> +#include <linux/platform_device.h>
>
> #include <asm/io.h>
> #include <asm/irq.h>
> #include <asm/mach-types.h>
>
> -#include <mach/addr-map.h>
> -
> -#define GPIO_NAND_CS (11)
> -#define GPIO_NAND_RB (89)
> +static struct gpio_desc *gpiod_nand_cs;
> +static struct gpio_desc *gpiod_nand_rb;
>
> /* MTD structure for CM-X270 board */
> static struct mtd_info *cmx270_nand_mtd;
> @@ -70,14 +69,14 @@ static void cmx270_read_buf(struct nand_chip *this, u_char *buf, int len)
>
> static inline void nand_cs_on(void)
> {
> - gpio_set_value(GPIO_NAND_CS, 0);
> + gpiod_set_value(gpiod_nand_cs, 0);
> }
>
> static void nand_cs_off(void)
> {
> dsb();
>
> - gpio_set_value(GPIO_NAND_CS, 1);
> + gpiod_set_value(gpiod_nand_cs, 1);
> }
>
> /*
> @@ -120,48 +119,41 @@ static int cmx270_device_ready(struct nand_chip *this)
> {
> dsb();
>
> - return (gpio_get_value(GPIO_NAND_RB));
> + return (gpiod_get_value(gpiod_nand_rb));
> }
>
> /*
> * Main initialization routine
> */
> -static int __init cmx270_init(void)
> +static int cmx270_probe(struct platform_device *pdev)
> {
> struct nand_chip *this;
> + struct device *dev = &pdev->dev;
> int ret;
>
> - if (!(machine_is_armcore() && cpu_is_pxa27x()))
> - return -ENODEV;
> -
> - ret = gpio_request(GPIO_NAND_CS, "NAND CS");
> + gpiod_nand_cs = devm_gpiod_get(dev, "cs", GPIOD_OUT_HIGH);
> + ret = PTR_ERR_OR_ZERO(gpiod_nand_cs);
> if (ret) {
> pr_warn("CM-X270: failed to request NAND CS gpio\n");
> return ret;
> }
>
> - gpio_direction_output(GPIO_NAND_CS, 1);
> -
> - ret = gpio_request(GPIO_NAND_RB, "NAND R/B");
> + gpiod_nand_rb = devm_gpiod_get(dev, "rb", GPIOD_IN);
> + ret = PTR_ERR_OR_ZERO(gpiod_nand_rb);
> if (ret) {
> pr_warn("CM-X270: failed to request NAND R/B gpio\n");
> - goto err_gpio_request;
> + return ret;
> }
>
> - gpio_direction_input(GPIO_NAND_RB);
> -
> /* Allocate memory for MTD device structure and private data */
> - this = kzalloc(sizeof(struct nand_chip), GFP_KERNEL);
> - if (!this) {
> - ret = -ENOMEM;
> - goto err_kzalloc;
> - }
> + this = devm_kzalloc(dev, sizeof(struct nand_chip), GFP_KERNEL);
> + if (!this)
> + return -ENOMEM;
>
> - cmx270_nand_io = ioremap(PXA_CS1_PHYS, 12);
> + cmx270_nand_io = devm_platform_ioremap_resource(pdev, 0);
> if (!cmx270_nand_io) {
> pr_debug("Unable to ioremap NAND device\n");
> - ret = -EINVAL;
> - goto err_ioremap;
> + return -EINVAL;
> }
>
> cmx270_nand_mtd = nand_to_mtd(this);
> @@ -189,48 +181,30 @@ static int __init cmx270_init(void)
> ret = nand_scan(this, 1);
> if (ret) {
> pr_notice("No NAND device\n");
> - goto err_scan;
> + return ret;
> }
>
> /* Register the partitions */
> - ret = mtd_device_register(cmx270_nand_mtd, partition_info,
> - NUM_PARTITIONS);
> - if (ret)
> - goto err_scan;
> -
> - /* Return happy */
> - return 0;
> -
> -err_scan:
> - iounmap(cmx270_nand_io);
> -err_ioremap:
> - kfree(this);
> -err_kzalloc:
> - gpio_free(GPIO_NAND_RB);
> -err_gpio_request:
> - gpio_free(GPIO_NAND_CS);
> -
> - return ret;
> -
> + return mtd_device_register(cmx270_nand_mtd, partition_info,
> + NUM_PARTITIONS);
> }
> -module_init(cmx270_init);
>
> /*
> * Clean up routine
> */
> -static void __exit cmx270_cleanup(void)
> +static int cmx270_remove(struct platform_device *pdev)
> {
> - /* Release resources, unregister device */
> nand_release(mtd_to_nand(cmx270_nand_mtd));
>
> - gpio_free(GPIO_NAND_RB);
> - gpio_free(GPIO_NAND_CS);
> -
> - iounmap(cmx270_nand_io);
> -
> - kfree(mtd_to_nand(cmx270_nand_mtd));
> + return 0;
> }
> -module_exit(cmx270_cleanup);
> +
> +static struct platform_driver cmx270_nand_driver = {
> + .driver.name = "cmx270-nand",
> + .probe = cmx270_probe,
> + .remove = cmx270_remove,
> +};
> +module_platform_driver(cmx270_nand_driver);
>
> MODULE_LICENSE("GPL");
> MODULE_AUTHOR("Mike Rapoport <mike@compulab.co.il>");

Thanks,
Miquèl