Re: [PATCH 2/2] mmc: JZ4740: Add support for JZ4775 and rename unreasonable array name.

[Paul Cercueil <paul@opendingux.net>]

Hi Zhou,

Le lun., juin 7 2021 at 02:08:04 +0800, 周琰杰 (Zhou Yanjie) 
<zhouyanjie@wanyeetech.com> a écrit :
> 1.Add support for probing mmc driver on the JZ4775 SoC from Ingenic.
> 2.When the support for JZ4775 SoC is added, there will be six 
> compatible
>   strings, so renaming "jz4740_mmc_of_match[]" to 
> "jz4740_mmc_of_matches[]"
>   is more reasonable.

Honestly, you can drop #2. We don't really care about the 
variable/function names not being "perfect". For instance this driver 
still use "jz4740_mmc*" functions everywhere even though it supports 
many more SoCs. Besides, renames like that makes it harder to "git 
blame" afterwards since it fills the git history with non-functional 
changes.

> 
> Signed-off-by: 周琰杰 (Zhou Yanjie) <zhouyanjie@wanyeetech.com>
> ---
>  drivers/mmc/host/jz4740_mmc.c | 25 ++++++++++++++-----------
>  1 file changed, 14 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/mmc/host/jz4740_mmc.c 
> b/drivers/mmc/host/jz4740_mmc.c
> index b3c636e..ea8434f 100644
> --- a/drivers/mmc/host/jz4740_mmc.c
> +++ b/drivers/mmc/host/jz4740_mmc.c
> @@ -2,6 +2,7 @@
>  /*
>   *  Copyright (C) 2009-2010, Lars-Peter Clausen <lars@metafoo.de>
>   *  Copyright (C) 2013, Imagination Technologies
> + *  Copyright (C) 2021, 周琰杰 (Zhou Yanjie) 
> <zhouyanjie@wanyeetech.com>
>   *
>   *  JZ4740 SD/MMC controller driver
>   */
> @@ -114,6 +115,7 @@ enum jz4740_mmc_version {
>  	JZ_MMC_JZ4740,
>  	JZ_MMC_JZ4725B,
>  	JZ_MMC_JZ4760,
> +	JZ_MMC_JZ4775,
>  	JZ_MMC_JZ4780,
>  	JZ_MMC_X1000,
>  };
> @@ -138,7 +140,7 @@ enum jz4740_mmc_state {
>   * COOKIE_MAPPED: the request was mapped in the irq handler,
>   * and should be unmapped before mmc_request_done is called..
>   */
> -enum jz4780_cookie {
> +enum jz4775_cookie {
>  	COOKIE_UNMAPPED = 0,
>  	COOKIE_PREMAPPED,
>  	COOKIE_MAPPED,
> @@ -194,7 +196,7 @@ static void jz4740_mmc_write_irq_mask(struct 
> jz4740_mmc_host *host,
>  static void jz4740_mmc_write_irq_reg(struct jz4740_mmc_host *host,
>  				     uint32_t val)
>  {
> -	if (host->version >= JZ_MMC_JZ4780)
> +	if (host->version >= JZ_MMC_JZ4775)
>  		writel(val, host->base + JZ_REG_MMC_IREG);
>  	else
>  		writew(val, host->base + JZ_REG_MMC_IREG);
> @@ -202,7 +204,7 @@ static void jz4740_mmc_write_irq_reg(struct 
> jz4740_mmc_host *host,
> 
>  static uint32_t jz4740_mmc_read_irq_reg(struct jz4740_mmc_host *host)
>  {
> -	if (host->version >= JZ_MMC_JZ4780)
> +	if (host->version >= JZ_MMC_JZ4775)
>  		return readl(host->base + JZ_REG_MMC_IREG);
>  	else
>  		return readw(host->base + JZ_REG_MMC_IREG);
> @@ -674,7 +676,7 @@ static void jz4740_mmc_send_command(struct 
> jz4740_mmc_host *host,
>  			cmdat |= JZ_MMC_CMDAT_WRITE;
>  		if (host->use_dma) {
>  			/*
> -			 * The 4780's MMC controller has integrated DMA ability
> +			 * The JZ4775's MMC controller has integrated DMA ability
>  			 * in addition to being able to use the external DMA
>  			 * controller. It moves DMA control bits to a separate
>  			 * register. The DMA_SEL bit chooses the external
> @@ -682,13 +684,13 @@ static void jz4740_mmc_send_command(struct 
> jz4740_mmc_host *host,
>  			 * can only use the external controller, and have a
>  			 * single DMA enable bit in CMDAT.
>  			 */
> -			if (host->version >= JZ_MMC_JZ4780) {
> +			if (host->version >= JZ_MMC_JZ4775) {
>  				writel(JZ_MMC_DMAC_DMA_EN | JZ_MMC_DMAC_DMA_SEL,
>  				       host->base + JZ_REG_MMC_DMAC);
>  			} else {
>  				cmdat |= JZ_MMC_CMDAT_DMA_EN;
>  			}
> -		} else if (host->version >= JZ_MMC_JZ4780) {
> +		} else if (host->version >= JZ_MMC_JZ4775) {
>  			writel(0, host->base + JZ_REG_MMC_DMAC);
>  		}
> 
> @@ -866,7 +868,7 @@ static int jz4740_mmc_set_clock_rate(struct 
> jz4740_mmc_host *host, int rate)
>  	writew(div, host->base + JZ_REG_MMC_CLKRT);
> 
>  	if (real_rate > 25000000) {
> -		if (host->version >= JZ_MMC_X1000) {
> +		if (host->version >= JZ_MMC_JZ4775) {

This changes the behaviour for the JZ4780.

Even if it is correct, this belongs in its own commit (with a Fixes 
tag), or at the very least a mention about it in the commit message.

>  			writel(JZ_MMC_LPM_DRV_RISING_QTR_PHASE_DLY |
>  				   JZ_MMC_LPM_SMP_RISING_QTR_OR_HALF_PHASE_DLY |
>  				   JZ_MMC_LPM_LOW_POWER_MODE_EN,
> @@ -955,15 +957,16 @@ static const struct mmc_host_ops jz4740_mmc_ops 
> = {
>  	.enable_sdio_irq = jz4740_mmc_enable_sdio_irq,
>  };
> 
> -static const struct of_device_id jz4740_mmc_of_match[] = {
> +static const struct of_device_id jz4740_mmc_of_matches[] = {
>  	{ .compatible = "ingenic,jz4740-mmc", .data = (void *) 
> JZ_MMC_JZ4740 },
>  	{ .compatible = "ingenic,jz4725b-mmc", .data = (void 
> *)JZ_MMC_JZ4725B },
>  	{ .compatible = "ingenic,jz4760-mmc", .data = (void *) 
> JZ_MMC_JZ4760 },
> +	{ .compatible = "ingenic,jz4775-mmc", .data = (void *) 
> JZ_MMC_JZ4775 },
>  	{ .compatible = "ingenic,jz4780-mmc", .data = (void *) 
> JZ_MMC_JZ4780 },

Looks to me that the JZ4775 and JZ4780 have the exact same behaviour, 
so this patch could have been a one-liner, adding "ingenic,jz4775-mmc" 
with the JZ_MMC_JZ4780 ID.

Cheers,
-Paul

>  	{ .compatible = "ingenic,x1000-mmc", .data = (void *) JZ_MMC_X1000 
> },
>  	{},
>  };
> -MODULE_DEVICE_TABLE(of, jz4740_mmc_of_match);
> +MODULE_DEVICE_TABLE(of, jz4740_mmc_of_matches);
> 
>  static int jz4740_mmc_probe(struct platform_device* pdev)
>  {
> @@ -980,7 +983,7 @@ static int jz4740_mmc_probe(struct 
> platform_device* pdev)
> 
>  	host = mmc_priv(mmc);
> 
> -	match = of_match_device(jz4740_mmc_of_match, &pdev->dev);
> +	match = of_match_device(jz4740_mmc_of_matches, &pdev->dev);
>  	if (match) {
>  		host->version = (enum jz4740_mmc_version)match->data;
>  	} else {
> @@ -1124,7 +1127,7 @@ static struct platform_driver jz4740_mmc_driver 
> = {
>  	.driver = {
>  		.name = "jz4740-mmc",
>  		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
> -		.of_match_table = of_match_ptr(jz4740_mmc_of_match),
> +		.of_match_table = of_match_ptr(jz4740_mmc_of_matches),
>  		.pm = pm_ptr(&jz4740_mmc_pm_ops),
>  	},
>  };
> --
> 2.7.4
>