Date:   Wed, 16 Mar 2022 23:46:55 +0000
From:   Paul Cercueil <paul@...pouillou.net>
To:     Aidan MacDonald <aidanmacdonald.0x0@...il.com>
Cc:     linus.walleij@...aro.org, linux-mips@...r.kernel.org,
        linux-gpio@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v3] pinctrl: ingenic: Fix regmap on X series SoCs

Hi Aidan,

Le mer., mars 16 2022 at 23:20:30 +0000, Aidan MacDonald 
<aidanmacdonald.0x0@...il.com> a écrit :
> The X series Ingenic SoCs have a shadow GPIO group which is at a 
> higher
> offset than the other groups, and is used for all GPIO configuration.
> The regmap did not take this offset into account and set max_register
> too low, so the regmap API blocked writes to the shadow group, which
> made the pinctrl driver unable to configure any pins.
> 
> Fix this by adding regmap access tables to the chip info.
> 
> Signed-off-by: Aidan MacDonald <aidanmacdonald.0x0@...il.com>

Since this is a fix, you need to add a Fixes: tag that points to the 
commit that introduced the bug, and add a Cc: <stable@...r.kernel.org> 
line as well.

> ---
> v1 -> v2: use regmap_access_table
> v2 -> v3: compute max_register instead of putting it in chip_info
> 
>  drivers/pinctrl/pinctrl-ingenic.c | 46 
> ++++++++++++++++++++++++++++++-
>  1 file changed, 45 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/pinctrl/pinctrl-ingenic.c 
> b/drivers/pinctrl/pinctrl-ingenic.c
> index 2712f51eb238..fa6becca1788 100644
> --- a/drivers/pinctrl/pinctrl-ingenic.c
> +++ b/drivers/pinctrl/pinctrl-ingenic.c
> @@ -119,6 +119,8 @@ struct ingenic_chip_info {
>  	unsigned int num_functions;
> 
>  	const u32 *pull_ups, *pull_downs;
> +
> +	const struct regmap_access_table *access_table;
>  };
> 
>  struct ingenic_pinctrl {
> @@ -2179,6 +2181,17 @@ static const struct function_desc 
> x1000_functions[] = {
>  	{ "mac", x1000_mac_groups, ARRAY_SIZE(x1000_mac_groups), },
>  };
> 
> +static const struct regmap_range x1000_access_ranges[] = {
> +	regmap_reg_range(0x000, 0x400 - 4),
> +	regmap_reg_range(0x700, 0x800 - 4),
> +};
> +
> +/* shared with X1500 */
> +static const struct regmap_access_table x1000_access_table = {
> +	.yes_ranges = x1000_access_ranges,
> +	.n_yes_ranges = ARRAY_SIZE(x1000_access_ranges),
> +};
> +
>  static const struct ingenic_chip_info x1000_chip_info = {
>  	.num_chips = 4,
>  	.reg_offset = 0x100,
> @@ -2189,6 +2202,7 @@ static const struct ingenic_chip_info 
> x1000_chip_info = {
>  	.num_functions = ARRAY_SIZE(x1000_functions),
>  	.pull_ups = x1000_pull_ups,
>  	.pull_downs = x1000_pull_downs,
> +	.access_table = &x1000_access_table,
>  };
> 
>  static int x1500_uart0_data_pins[] = { 0x4a, 0x4b, };
> @@ -2300,6 +2314,7 @@ static const struct ingenic_chip_info 
> x1500_chip_info = {
>  	.num_functions = ARRAY_SIZE(x1500_functions),
>  	.pull_ups = x1000_pull_ups,
>  	.pull_downs = x1000_pull_downs,
> +	.access_table = &x1000_access_table,
>  };
> 
>  static const u32 x1830_pull_ups[4] = {
> @@ -2506,6 +2521,16 @@ static const struct function_desc 
> x1830_functions[] = {
>  	{ "mac", x1830_mac_groups, ARRAY_SIZE(x1830_mac_groups), },
>  };
> 
> +static const struct regmap_range x1830_access_ranges[] = {
> +	regmap_reg_range(0x0000, 0x4000 - 4),
> +	regmap_reg_range(0x7000, 0x8000 - 4),
> +};
> +
> +static const struct regmap_access_table x1830_access_table = {
> +	.yes_ranges = x1830_access_ranges,
> +	.n_yes_ranges = ARRAY_SIZE(x1830_access_ranges),
> +};
> +
>  static const struct ingenic_chip_info x1830_chip_info = {
>  	.num_chips = 4,
>  	.reg_offset = 0x1000,
> @@ -2516,6 +2541,7 @@ static const struct ingenic_chip_info 
> x1830_chip_info = {
>  	.num_functions = ARRAY_SIZE(x1830_functions),
>  	.pull_ups = x1830_pull_ups,
>  	.pull_downs = x1830_pull_downs,
> +	.access_table = &x1830_access_table,
>  };
> 
>  static const u32 x2000_pull_ups[5] = {
> @@ -2969,6 +2995,17 @@ static const struct function_desc 
> x2000_functions[] = {
>  	{ "otg", x2000_otg_groups, ARRAY_SIZE(x2000_otg_groups), },
>  };
> 
> +static const struct regmap_range x2000_access_ranges[] = {
> +	regmap_reg_range(0x000, 0x500 - 4),
> +	regmap_reg_range(0x700, 0x800 - 4),
> +};
> +
> +/* shared with X2100 */
> +static const struct regmap_access_table x2000_access_table = {
> +	.yes_ranges = x2000_access_ranges,
> +	.n_yes_ranges = ARRAY_SIZE(x2000_access_ranges),
> +};
> +
>  static const struct ingenic_chip_info x2000_chip_info = {
>  	.num_chips = 5,
>  	.reg_offset = 0x100,
> @@ -2979,6 +3016,7 @@ static const struct ingenic_chip_info 
> x2000_chip_info = {
>  	.num_functions = ARRAY_SIZE(x2000_functions),
>  	.pull_ups = x2000_pull_ups,
>  	.pull_downs = x2000_pull_downs,
> +	.access_table = &x2000_access_table,
>  };
> 
>  static const u32 x2100_pull_ups[5] = {
> @@ -3189,6 +3227,7 @@ static const struct ingenic_chip_info 
> x2100_chip_info = {
>  	.num_functions = ARRAY_SIZE(x2100_functions),
>  	.pull_ups = x2100_pull_ups,
>  	.pull_downs = x2100_pull_downs,
> +	.access_table = &x2000_access_table,
>  };
> 
>  static u32 ingenic_gpio_read_reg(struct ingenic_gpio_chip *jzgc, u8 
> reg)
> @@ -4168,7 +4207,12 @@ static int __init ingenic_pinctrl_probe(struct 
> platform_device *pdev)
>  		return PTR_ERR(base);
> 
>  	regmap_config = ingenic_pinctrl_regmap_config;
> -	regmap_config.max_register = chip_info->num_chips * 
> chip_info->reg_offset;
> +	if (chip_info->access_table) {
> +		regmap_config.rd_table = chip_info->access_table;
> +		regmap_config.wr_table = chip_info->access_table;
> +	} else {
> +		regmap_config.max_register = chip_info->num_chips * 
> chip_info->reg_offset - 4;

You do actually change how regmap_config.max_register is computed here, 
without explaining anywhere why it is changed. I'm not saying that it's 
wrong, but you should explain in the commit message why this is changed.

Cheers,
-Paul

> +	}
> 
>  	jzpc->map = devm_regmap_init_mmio(dev, base, &regmap_config);
>  	if (IS_ERR(jzpc->map)) {
> --
> 2.34.1
> 

Powered by blists - more mailing lists