[U-Boot] [PATCH v2 4/5] imx: pinctrl: Add support for i.MX28 mxs pinctrl driver

Lukasz Majewski
2019-06-14T06:49:31Z

The code responsible for setting proper values in the MUX registers
(in the mxs_pinctrl_set_state()) has been ported from Barebox project
(branch: master, SHA1: eb3b0f7414cd8102844dd16b1c789e445e8947f8,
file: drivers/pinctrl/pinctrl-mxs.c).

As the pinctrl node in the imx28.dtsi file has gpio pins nodes as subnodes,
it was necessary to use 'dm_scan_fdt_dev()' (as a .bind method) to also
make them 'visible' by the DM's "gpio_mxs" driver.

Signed-off-by: Lukasz Majewski <lukma@denx.de>
---

Changes in v2: None

drivers/pinctrl/nxp/Kconfig | 10 +++
drivers/pinctrl/nxp/Makefile | 1 +
drivers/pinctrl/nxp/pinctrl-mxs.c | 164 ++++++++++++++++++++++++++++++++++++++
3 files changed, 175 insertions(+)
create mode 100644 drivers/pinctrl/nxp/pinctrl-mxs.c

diff --git a/drivers/pinctrl/nxp/Kconfig b/drivers/pinctrl/nxp/Kconfig
index 61f93be42d..f2e67ca231 100644
--- a/drivers/pinctrl/nxp/Kconfig
+++ b/drivers/pinctrl/nxp/Kconfig
@@ -89,6 +89,16 @@ config PINCTRL_IMX8M
only parses the 'fsl,pins' property and configure related
registers.

+config PINCTRL_MXS
+ bool "NXP MXS pinctrl driver"
+ depends on ARCH_MX28 && PINCTRL_FULL
+ help
+ Say Y here to enable the i.MX mxs pinctrl driver
+
+ This option provides a simple pinctrl driver for i.MX mxs SoC
+ familiy, e.g. i.MX28. This feature depends on device tree
+ configuration.
+
config PINCTRL_VYBRID
bool "Vybrid (vf610) pinctrl driver"
depends on ARCH_VF610 && PINCTRL_FULL
diff --git a/drivers/pinctrl/nxp/Makefile b/drivers/pinctrl/nxp/Makefile
index b340d9448a..b86448aac9 100644
--- a/drivers/pinctrl/nxp/Makefile
+++ b/drivers/pinctrl/nxp/Makefile
@@ -6,4 +6,5 @@ obj-$(CONFIG_PINCTRL_IMX7ULP) += pinctrl-imx7ulp.o
obj-$(CONFIG_PINCTRL_IMX_SCU) += pinctrl-scu.o
obj-$(CONFIG_PINCTRL_IMX8) += pinctrl-imx8.o
obj-$(CONFIG_PINCTRL_IMX8M) += pinctrl-imx8m.o
+obj-$(CONFIG_PINCTRL_MXS) += pinctrl-mxs.o
obj-$(CONFIG_PINCTRL_VYBRID) += pinctrl-vf610.o
diff --git a/drivers/pinctrl/nxp/pinctrl-mxs.c b/drivers/pinctrl/nxp/pinctrl-mxs.c
new file mode 100644
index 0000000000..42b1b7998b
--- /dev/null
+++ b/drivers/pinctrl/nxp/pinctrl-mxs.c
@@ -0,0 +1,164 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 DENX Software Engineering
+ * Lukasz Majewski, DENX Software Engineering, lukma at denx.de
+ *
+ * This work is based on drivers/pinctrl/pinctrl-mxs.c
+ * SHA1: eb3b0f7414cd8102844dd16b1c789e445e8947f8
+ * from Barebox project.
+ *
+ * Author of original Barebox pinctrl-mxs.c:
+ * Copyright (c) 2015 Sascha Hauer <s.hauer@pengutronix.de>
+ */
+
+#include <common.h>
+#include <linux/io.h>
+#include <linux/err.h>
+#include <dm.h>
+#include <dm/pinctrl.h>
+#include <dm/read.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#define PINID(bank, pin) ((bank) * 32 + (pin))
+#define MUXID_TO_PINID(m) PINID((m) >> 12 & 0xf, (m) >> 4 & 0xff)
+#define MUXID_TO_MUXSEL(m) ((m) & 0xf)
+#define PINID_TO_BANK(p) ((p) >> 5)
+#define PINID_TO_PIN(p) ((p) % 32)
+
+#define STMP_OFFSET_REG_SET 0x4
+#define STMP_OFFSET_REG_CLR 0x8
+#define STMP_OFFSET_REG_TOG 0xc
+
+struct mxs_pinctrl_priv {
+ void __iomem *base;
+};
+
+static int mxs_pinctrl_set_state(struct udevice *dev, struct udevice *config)
+{
+ int ma_present = 0, vol_present = 0, pull_present = 0;
+ struct mxs_pinctrl_priv *iomux = dev_get_priv(dev);
+ u32 *pin_data, val, ma, vol, pull;
+ int npins, size, i, ret;
+
+ debug("\n%s: set state: %s\n", __func__, config->name);
+
+ size = dev_read_size(config, "fsl,pinmux-ids");
+ if (size < 0)
+ return size;
+
+ if (!size || size % 4) {
+ dev_err(dev, "Invalid fsl,pinmux-ids property in %s\n",
+ config->name);
+ return -EINVAL;
+ }
+
+ npins = size / 4;
+
+ pin_data = devm_kzalloc(dev, size, 0);
+ if (!pin_data)
+ return -ENOMEM;
+
+ ret = dev_read_u32_array(config, "fsl,pinmux-ids", pin_data, npins);
+ if (ret) {
+ dev_err(dev, "Error reading pin data.\n");
+ devm_kfree(dev, pin_data);
+ return -EINVAL;
+ }
+
+ ret = dev_read_u32(config, "fsl,drive-strength", &ma);
+ if (!ret)
+ ma_present = 1;
+
+ ret = dev_read_u32(config, "fsl,voltage", &vol);
+ if (!ret)
+ vol_present = 1;
+
+ ret = dev_read_u32(config, "fsl,pull-up", &pull);
+ if (!ret)
+ pull_present = 1;
+
+ for (i = 0; i < npins; i++) {
+ int muxsel, pinid, bank, pin, shift;
+ void __iomem *reg;
+
+ val = *pin_data++;
+
+ muxsel = MUXID_TO_MUXSEL(val);
+ pinid = MUXID_TO_PINID(val);
+
+ bank = PINID_TO_BANK(pinid);
+ pin = PINID_TO_PIN(pinid);
+ reg = iomux->base + 0x100;
+ reg += bank * 0x20 + pin / 16 * 0x10;
+ shift = pin % 16 * 2;
+
+ writel(0x3 << shift, reg + STMP_OFFSET_REG_CLR);
+ writel(muxsel << shift, reg + STMP_OFFSET_REG_SET);
+
+ debug("(val: 0x%x) pin %d, mux %d, ma: %d, vol: %d, pull: %d\n",
+ val, pinid, muxsel, ma, vol, pull);
+
+ /* drive */
+ reg = iomux->base + 0x300;
+ reg += bank * 0x40 + pin / 8 * 0x10;
+
+ /* mA */
+ if (ma_present) {
+ shift = pin % 8 * 4;
+ writel(0x3 << shift, reg + STMP_OFFSET_REG_CLR);
+ writel(ma << shift, reg + STMP_OFFSET_REG_SET);
+ }
+
+ /* vol */
+ if (vol_present) {
+ shift = pin % 8 * 4 + 2;
+ if (vol)
+ writel(1 << shift, reg + STMP_OFFSET_REG_SET);
+ else
+ writel(1 << shift, reg + STMP_OFFSET_REG_CLR);
+ }
+
+ /* pull */
+ if (pull_present) {
+ reg = iomux->base + 0x600;
+ reg += bank * 0x10;
+ shift = pin;
+ if (pull)
+ writel(1 << shift, reg + STMP_OFFSET_REG_SET);
+ else
+ writel(1 << shift, reg + STMP_OFFSET_REG_CLR);
+ }
+ }
+
+ return 0;
+}
+
+static struct pinctrl_ops mxs_pinctrl_ops = {
+ .set_state = mxs_pinctrl_set_state,
+};
+
+static int mxs_pinctrl_probe(struct udevice *dev)
+{
+ struct mxs_pinctrl_priv *iomux = dev_get_priv(dev);
+ iomux->base = dev_read_addr_ptr(dev);
+
+ return 0;
+}
+
+static const struct udevice_id mxs_pinctrl_match[] = {
+ { .compatible = "fsl,imx28-pinctrl" },
+ { /* sentinel */ }
+};
+
+U_BOOT_DRIVER(mxs_pinctrl) = {
+ .name = "mxs-pinctrl",
+ .id = UCLASS_PINCTRL,
+ .of_match = of_match_ptr(mxs_pinctrl_match),
+ .probe = mxs_pinctrl_probe,
+#if !CONFIG_IS_ENABLED(OF_PLATDATA)
+ .bind = dm_scan_fdt_dev,
+#endif
+ .priv_auto_alloc_size = sizeof(struct mxs_pinctrl_priv),
+ .ops = &mxs_pinctrl_ops,
+};
--
2.11.0