2022-09-08 15:16:24

by Kavyasree Kotagiri

[permalink] [raw]
Subject: [RESEND PATCH v9 3/3] mfd: atmel-flexcom: Add support for lan966x flexcom chip-select configuration

LAN966x SoC have 5 flexcoms. Each flexcom has 2 chip-selects
which are optional I/O lines. For each chip select of each
flexcom there is a configuration register FLEXCOM_SHARED[0-4]:SS_MASK[0-1].
The width of configuration register is 21 because there are
21 shared pins on each of which the chip select can be mapped.
Each bit of the register represents a different FLEXCOM_SHARED pin.

Signed-off-by: Kavyasree Kotagiri <[email protected]>
---
v8 -> v9:
- No changes.

v7 -> v8:
- Changed compatible string to microchip,lan9668-flexcom.

v6 -> v7:
- No changes.

v5 -> v6:
- No changes.

v4 -> v5:
- No changes.

v3 -> v4:
- Add condition for a flexcom whether to configure chip-select lines
or not, based on "microchip,flx-shrd-pins" property existence because
chip-select lines are optional.

v2 -> v3:
- used goto label for clk_disable in error cases.

v1 -> v2:
- use GENMASK for mask, macros for maximum allowed values.
- use u32 values for flexcom chipselects instead of strings.
- disable clock in case of errors.

drivers/mfd/atmel-flexcom.c | 94 ++++++++++++++++++++++++++++++++++++-
1 file changed, 93 insertions(+), 1 deletion(-)

diff --git a/drivers/mfd/atmel-flexcom.c b/drivers/mfd/atmel-flexcom.c
index 33caa4fba6af..92ea15d5fd72 100644
--- a/drivers/mfd/atmel-flexcom.c
+++ b/drivers/mfd/atmel-flexcom.c
@@ -28,15 +28,68 @@
#define FLEX_MR_OPMODE(opmode) (((opmode) << FLEX_MR_OPMODE_OFFSET) & \
FLEX_MR_OPMODE_MASK)

+/* LAN966x flexcom shared register offsets */
+#define FLEX_SHRD_SS_MASK_0 0x0
+#define FLEX_SHRD_SS_MASK_1 0x4
+#define FLEX_SHRD_PIN_MAX 20
+#define FLEX_CS_MAX 1
+#define FLEX_SHRD_MASK GENMASK(20, 0)
+
+struct atmel_flex_caps {
+ bool has_flx_cs;
+};
+
struct atmel_flexcom {
void __iomem *base;
+ void __iomem *flexcom_shared_base;
u32 opmode;
struct clk *clk;
};

+static int atmel_flexcom_lan966x_cs_config(struct platform_device *pdev)
+{
+ struct atmel_flexcom *ddata = dev_get_drvdata(&pdev->dev);
+ struct device_node *np = pdev->dev.of_node;
+ u32 flx_shrd_pins[2], flx_cs[2], val;
+ int err, i, count;
+
+ count = of_property_count_u32_elems(np, "microchip,flx-shrd-pins");
+ if (count <= 0 || count > 2) {
+ dev_err(&pdev->dev, "Invalid %s property (%d)\n", "flx-shrd-pins",
+ count);
+ return -EINVAL;
+ }
+
+ err = of_property_read_u32_array(np, "microchip,flx-shrd-pins", flx_shrd_pins, count);
+ if (err)
+ return err;
+
+ err = of_property_read_u32_array(np, "microchip,flx-cs", flx_cs, count);
+ if (err)
+ return err;
+
+ for (i = 0; i < count; i++) {
+ if (flx_shrd_pins[i] > FLEX_SHRD_PIN_MAX)
+ return -EINVAL;
+
+ if (flx_cs[i] > FLEX_CS_MAX)
+ return -EINVAL;
+
+ val = ~(1 << flx_shrd_pins[i]) & FLEX_SHRD_MASK;
+
+ if (flx_cs[i] == 0)
+ writel(val, ddata->flexcom_shared_base + FLEX_SHRD_SS_MASK_0);
+ else
+ writel(val, ddata->flexcom_shared_base + FLEX_SHRD_SS_MASK_1);
+ }
+
+ return 0;
+}
+
static int atmel_flexcom_probe(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
+ const struct atmel_flex_caps *caps;
struct resource *res;
struct atmel_flexcom *ddata;
int err;
@@ -76,13 +129,52 @@ static int atmel_flexcom_probe(struct platform_device *pdev)
*/
writel(FLEX_MR_OPMODE(ddata->opmode), ddata->base + FLEX_MR);

+ caps = of_device_get_match_data(&pdev->dev);
+ if (!caps) {
+ dev_err(&pdev->dev, "Could not retrieve flexcom caps\n");
+ err = -EINVAL;
+ goto clk_disable;
+ }
+
+ if (caps->has_flx_cs && of_property_read_bool(np, "microchip,flx-shrd-pins")) {
+ ddata->flexcom_shared_base = devm_platform_get_and_ioremap_resource(pdev, 1, NULL);
+ if (IS_ERR(ddata->flexcom_shared_base)) {
+ err = dev_err_probe(&pdev->dev,
+ PTR_ERR(ddata->flexcom_shared_base),
+ "failed to get flexcom shared base address\n");
+ goto clk_disable;
+ }
+
+ err = atmel_flexcom_lan966x_cs_config(pdev);
+ if (err)
+ goto clk_disable;
+ }
+
+clk_disable:
clk_disable_unprepare(ddata->clk);
+ if (err)
+ return err;

return devm_of_platform_populate(&pdev->dev);
}

+static const struct atmel_flex_caps atmel_flexcom_caps = {};
+
+static const struct atmel_flex_caps lan966x_flexcom_caps = {
+ .has_flx_cs = true,
+};
+
static const struct of_device_id atmel_flexcom_of_match[] = {
- { .compatible = "atmel,sama5d2-flexcom" },
+ {
+ .compatible = "atmel,sama5d2-flexcom",
+ .data = &atmel_flexcom_caps,
+ },
+
+ {
+ .compatible = "microchip,lan9668-flexcom",
+ .data = &lan966x_flexcom_caps,
+ },
+
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, atmel_flexcom_of_match);
--
2.25.1


2022-09-08 16:10:45

by Kavyasree Kotagiri

[permalink] [raw]
Subject: RE: [RESEND PATCH v9 3/3] mfd: atmel-flexcom: Add support for lan966x flexcom chip-select configuration

> Subject: [RESEND PATCH v9 3/3] mfd: atmel-flexcom: Add support for
> lan966x flexcom chip-select configuration
>
> LAN966x SoC have 5 flexcoms. Each flexcom has 2 chip-selects
> which are optional I/O lines. For each chip select of each
> flexcom there is a configuration register FLEXCOM_SHARED[0-4]:SS_MASK[0-
> 1].
> The width of configuration register is 21 because there are
> 21 shared pins on each of which the chip select can be mapped.
> Each bit of the register represents a different FLEXCOM_SHARED pin.
>
> Signed-off-by: Kavyasree Kotagiri <[email protected]>

Missed adding tag - Reviewed-by: Claudiu Beznea <[email protected]>

> ---
> v8 -> v9:
> - No changes.
>
> v7 -> v8:
> - Changed compatible string to microchip,lan9668-flexcom.
>
> v6 -> v7:
> - No changes.
>
> v5 -> v6:
> - No changes.
>
> v4 -> v5:
> - No changes.
>
> v3 -> v4:
> - Add condition for a flexcom whether to configure chip-select lines
> or not, based on "microchip,flx-shrd-pins" property existence because
> chip-select lines are optional.
>
> v2 -> v3:
> - used goto label for clk_disable in error cases.
>
> v1 -> v2:
> - use GENMASK for mask, macros for maximum allowed values.
> - use u32 values for flexcom chipselects instead of strings.
> - disable clock in case of errors.
>
> drivers/mfd/atmel-flexcom.c | 94
> ++++++++++++++++++++++++++++++++++++-
> 1 file changed, 93 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/mfd/atmel-flexcom.c b/drivers/mfd/atmel-flexcom.c
> index 33caa4fba6af..92ea15d5fd72 100644
> --- a/drivers/mfd/atmel-flexcom.c
> +++ b/drivers/mfd/atmel-flexcom.c
> @@ -28,15 +28,68 @@
> #define FLEX_MR_OPMODE(opmode) (((opmode) <<
> FLEX_MR_OPMODE_OFFSET) & \
> FLEX_MR_OPMODE_MASK)
>
> +/* LAN966x flexcom shared register offsets */
> +#define FLEX_SHRD_SS_MASK_0 0x0
> +#define FLEX_SHRD_SS_MASK_1 0x4
> +#define FLEX_SHRD_PIN_MAX 20
> +#define FLEX_CS_MAX 1
> +#define FLEX_SHRD_MASK GENMASK(20, 0)
> +
> +struct atmel_flex_caps {
> + bool has_flx_cs;
> +};
> +
> struct atmel_flexcom {
> void __iomem *base;
> + void __iomem *flexcom_shared_base;
> u32 opmode;
> struct clk *clk;
> };
>
> +static int atmel_flexcom_lan966x_cs_config(struct platform_device *pdev)
> +{
> + struct atmel_flexcom *ddata = dev_get_drvdata(&pdev->dev);
> + struct device_node *np = pdev->dev.of_node;
> + u32 flx_shrd_pins[2], flx_cs[2], val;
> + int err, i, count;
> +
> + count = of_property_count_u32_elems(np, "microchip,flx-shrd-
> pins");
> + if (count <= 0 || count > 2) {
> + dev_err(&pdev->dev, "Invalid %s property (%d)\n", "flx-shrd-
> pins",
> + count);
> + return -EINVAL;
> + }
> +
> + err = of_property_read_u32_array(np, "microchip,flx-shrd-pins",
> flx_shrd_pins, count);
> + if (err)
> + return err;
> +
> + err = of_property_read_u32_array(np, "microchip,flx-cs", flx_cs,
> count);
> + if (err)
> + return err;
> +
> + for (i = 0; i < count; i++) {
> + if (flx_shrd_pins[i] > FLEX_SHRD_PIN_MAX)
> + return -EINVAL;
> +
> + if (flx_cs[i] > FLEX_CS_MAX)
> + return -EINVAL;
> +
> + val = ~(1 << flx_shrd_pins[i]) & FLEX_SHRD_MASK;
> +
> + if (flx_cs[i] == 0)
> + writel(val, ddata->flexcom_shared_base +
> FLEX_SHRD_SS_MASK_0);
> + else
> + writel(val, ddata->flexcom_shared_base +
> FLEX_SHRD_SS_MASK_1);
> + }
> +
> + return 0;
> +}
> +
> static int atmel_flexcom_probe(struct platform_device *pdev)
> {
> struct device_node *np = pdev->dev.of_node;
> + const struct atmel_flex_caps *caps;
> struct resource *res;
> struct atmel_flexcom *ddata;
> int err;
> @@ -76,13 +129,52 @@ static int atmel_flexcom_probe(struct
> platform_device *pdev)
> */
> writel(FLEX_MR_OPMODE(ddata->opmode), ddata->base +
> FLEX_MR);
>
> + caps = of_device_get_match_data(&pdev->dev);
> + if (!caps) {
> + dev_err(&pdev->dev, "Could not retrieve flexcom caps\n");
> + err = -EINVAL;
> + goto clk_disable;
> + }
> +
> + if (caps->has_flx_cs && of_property_read_bool(np, "microchip,flx-
> shrd-pins")) {
> + ddata->flexcom_shared_base =
> devm_platform_get_and_ioremap_resource(pdev, 1, NULL);
> + if (IS_ERR(ddata->flexcom_shared_base)) {
> + err = dev_err_probe(&pdev->dev,
> + PTR_ERR(ddata-
> >flexcom_shared_base),
> + "failed to get flexcom shared base
> address\n");
> + goto clk_disable;
> + }
> +
> + err = atmel_flexcom_lan966x_cs_config(pdev);
> + if (err)
> + goto clk_disable;
> + }
> +
> +clk_disable:
> clk_disable_unprepare(ddata->clk);
> + if (err)
> + return err;
>
> return devm_of_platform_populate(&pdev->dev);
> }
>
> +static const struct atmel_flex_caps atmel_flexcom_caps = {};
> +
> +static const struct atmel_flex_caps lan966x_flexcom_caps = {
> + .has_flx_cs = true,
> +};
> +
> static const struct of_device_id atmel_flexcom_of_match[] = {
> - { .compatible = "atmel,sama5d2-flexcom" },
> + {
> + .compatible = "atmel,sama5d2-flexcom",
> + .data = &atmel_flexcom_caps,
> + },
> +
> + {
> + .compatible = "microchip,lan9668-flexcom",
> + .data = &lan966x_flexcom_caps,
> + },
> +
> { /* sentinel */ }
> };
> MODULE_DEVICE_TABLE(of, atmel_flexcom_of_match);
> --
> 2.25.1