[PATCH 4/4] mux: lan966: Add support for flexcom mux controller
Kavyasree Kotagiri
kavyasree.kotagiri at microchip.com
Tue May 3 03:55:28 PDT 2022
LAN966 SoC have 5 flexcoms. Each flexcom has 2 chip-selects.
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 <kavyasree.kotagiri at microchip.com>
---
arch/arm/mach-at91/Kconfig | 2 +
drivers/mfd/atmel-flexcom.c | 55 ++++++++++++++++-
drivers/mux/Kconfig | 12 ++++
drivers/mux/Makefile | 2 +
drivers/mux/lan966-flx.c | 116 ++++++++++++++++++++++++++++++++++++
5 files changed, 186 insertions(+), 1 deletion(-)
create mode 100644 drivers/mux/lan966-flx.c
diff --git a/arch/arm/mach-at91/Kconfig b/arch/arm/mach-at91/Kconfig
index 279810381256..26fb0f4e1b79 100644
--- a/arch/arm/mach-at91/Kconfig
+++ b/arch/arm/mach-at91/Kconfig
@@ -74,6 +74,8 @@ config SOC_LAN966
select DW_APB_TIMER_OF
select ARM_GIC
select MEMORY
+ select MULTIPLEXER
+ select MUX_LAN966
help
This enables support for ARMv7 based Microchip LAN966 SoC family.
diff --git a/drivers/mfd/atmel-flexcom.c b/drivers/mfd/atmel-flexcom.c
index 33caa4fba6af..cf3dac383f30 100644
--- a/drivers/mfd/atmel-flexcom.c
+++ b/drivers/mfd/atmel-flexcom.c
@@ -17,6 +17,7 @@
#include <linux/io.h>
#include <linux/clk.h>
#include <dt-bindings/mfd/atmel-flexcom.h>
+#include <linux/mux/consumer.h>
/* I/O register offsets */
#define FLEX_MR 0x0 /* Mode Register */
@@ -28,6 +29,10 @@
#define FLEX_MR_OPMODE(opmode) (((opmode) << FLEX_MR_OPMODE_OFFSET) & \
FLEX_MR_OPMODE_MASK)
+struct atmel_flex_caps {
+ bool has_flx_mux;
+};
+
struct atmel_flexcom {
void __iomem *base;
u32 opmode;
@@ -37,6 +42,7 @@ struct atmel_flexcom {
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 +82,60 @@ 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");
+ return -EINVAL;
+ }
+
+ /* Flexcom Mux */
+ if (caps->has_flx_mux && of_property_read_bool(np, "mux-controls")) {
+ struct mux_control *flx_mux;
+ struct of_phandle_args args;
+ int i, count;
+
+ flx_mux = devm_mux_control_get(&pdev->dev, NULL);
+ if (IS_ERR(flx_mux))
+ return PTR_ERR(flx_mux);
+
+ count = of_property_count_strings(np, "mux-control-names");
+ for (i = 0; i < count; i++) {
+ err = of_parse_phandle_with_fixed_args(np, "mux-controls", 1, i, &args);
+ if (err)
+ break;
+
+ err = mux_control_select(flx_mux, args.args[0]);
+ if (!err) {
+ mux_control_deselect(flx_mux);
+ } else {
+ dev_err(&pdev->dev, "Failed to select FLEXCOM mux\n");
+ return err;
+ }
+ }
+ }
+
clk_disable_unprepare(ddata->clk);
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_mux = 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,lan966-flexcom",
+ .data = &lan966x_flexcom_caps,
+ },
+
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, atmel_flexcom_of_match);
diff --git a/drivers/mux/Kconfig b/drivers/mux/Kconfig
index e5c571fd232c..ea09f474bc2f 100644
--- a/drivers/mux/Kconfig
+++ b/drivers/mux/Kconfig
@@ -45,6 +45,18 @@ config MUX_GPIO
To compile the driver as a module, choose M here: the module will
be called mux-gpio.
+config MUX_LAN966
+ tristate "LAN966 Flexcom multiplexer"
+ depends on OF || COMPILE_TEST
+ help
+ Lan966 Flexcom Multiplexer controller.
+
+ The driver supports mapping 2 chip-selects of each of the lan966
+ flexcoms to 21 flexcom shared pins.
+
+ To compile the driver as a module, choose M here: the module will
+ be called mux-lan966.
+
config MUX_MMIO
tristate "MMIO/Regmap register bitfield-controlled Multiplexer"
depends on OF || COMPILE_TEST
diff --git a/drivers/mux/Makefile b/drivers/mux/Makefile
index 6e9fa47daf56..53a9840d96fa 100644
--- a/drivers/mux/Makefile
+++ b/drivers/mux/Makefile
@@ -7,10 +7,12 @@ mux-core-objs := core.o
mux-adg792a-objs := adg792a.o
mux-adgs1408-objs := adgs1408.o
mux-gpio-objs := gpio.o
+mux-lan966-objs := lan966-flx.o
mux-mmio-objs := mmio.o
obj-$(CONFIG_MULTIPLEXER) += mux-core.o
obj-$(CONFIG_MUX_ADG792A) += mux-adg792a.o
obj-$(CONFIG_MUX_ADGS1408) += mux-adgs1408.o
obj-$(CONFIG_MUX_GPIO) += mux-gpio.o
+obj-$(CONFIG_MUX_LAN966) += mux-lan966.o
obj-$(CONFIG_MUX_MMIO) += mux-mmio.o
diff --git a/drivers/mux/lan966-flx.c b/drivers/mux/lan966-flx.c
new file mode 100644
index 000000000000..5d078a159fcd
--- /dev/null
+++ b/drivers/mux/lan966-flx.c
@@ -0,0 +1,116 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * LAN966 Flexcom MUX driver
+ *
+ * Copyright (c) Microchip Inc.
+ *
+ * Author: Kavyasree Kotagiri <kavyasree.kotagiri at microchip.com>
+ */
+
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+#include <linux/mux/driver.h>
+#include <linux/io.h>
+
+#define FLEX_SHRD_MASK 0x1FFFFF
+#define LAN966_MAX_CS 21
+
+static void __iomem *flx_shared_base;
+struct mux_lan966x {
+ u32 offset;
+ u32 ss_pin;
+};
+
+static int mux_lan966x_set(struct mux_control *mux, int state)
+{
+ struct mux_lan966x *mux_lan966x = mux_chip_priv(mux->chip);
+ u32 val;
+
+ val = ~(1 << mux_lan966x[state].ss_pin) & FLEX_SHRD_MASK;
+ writel(val, flx_shared_base + mux_lan966x[state].offset);
+
+ return 0;
+}
+
+static const struct mux_control_ops mux_lan966x_ops = {
+ .set = mux_lan966x_set,
+};
+
+static const struct of_device_id mux_lan966x_dt_ids[] = {
+ { .compatible = "microchip,lan966-flx-mux", },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, mux_lan966x_dt_ids);
+
+static int mux_lan966x_probe(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct device *dev = &pdev->dev;
+ struct mux_lan966x *mux_lan966x;
+ struct mux_chip *mux_chip;
+ int ret, num_fields, i;
+
+ ret = of_property_count_u32_elems(np, "mux-offset-pin");
+ if (ret == 0 || ret % 2)
+ ret = -EINVAL;
+ if (ret < 0)
+ return dev_err_probe(dev, ret,
+ "mux-offset-pin property missing or invalid");
+ num_fields = ret / 2;
+
+ mux_chip = devm_mux_chip_alloc(dev, num_fields, sizeof(*mux_lan966x));
+ if (IS_ERR(mux_chip))
+ return dev_err_probe(dev, PTR_ERR(mux_chip),
+ "failed to allocate mux_chips\n");
+
+ mux_lan966x = mux_chip_priv(mux_chip);
+
+ flx_shared_base = devm_platform_get_and_ioremap_resource(pdev, 0, NULL);
+ if (IS_ERR(flx_shared_base))
+ return dev_err_probe(dev, PTR_ERR(flx_shared_base),
+ "failed to get flexcom shared base address\n");
+
+ for (i = 0; i < num_fields; i++) {
+ struct mux_control *mux = &mux_chip->mux[i];
+ u32 offset, shared_pin;
+
+ ret = of_property_read_u32_index(np, "mux-offset-pin",
+ 2 * i, &offset);
+ if (ret == 0)
+ ret = of_property_read_u32_index(np, "mux-offset-pin",
+ 2 * i + 1,
+ &shared_pin);
+ if (ret < 0)
+ return dev_err_probe(dev, ret,
+ "failed to read mux-offset-pin property: %d", i);
+
+ if (shared_pin >= LAN966_MAX_CS)
+ return -EINVAL;
+
+ mux_lan966x[i].offset = offset;
+ mux_lan966x[i].ss_pin = shared_pin;
+
+ mux->states = LAN966_MAX_CS;
+ }
+
+ mux_chip->ops = &mux_lan966x_ops;
+
+ ret = devm_mux_chip_register(dev, mux_chip);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+static struct platform_driver mux_lan966x_driver = {
+ .driver = {
+ .name = "lan966-mux",
+ .of_match_table = of_match_ptr(mux_lan966x_dt_ids),
+ },
+ .probe = mux_lan966x_probe,
+};
+
+module_platform_driver(mux_lan966x_driver);
--
2.17.1
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