STiH410: Add STi pinctrl driver
authorPatrice Chotard <patrice.chotard@st.com>
Tue, 21 Feb 2017 12:37:10 +0000 (13:37 +0100)
committerTom Rini <trini@konsulko.com>
Wed, 15 Mar 2017 00:40:20 +0000 (20:40 -0400)
Add STMicroelectronics STiH410 pinctrl driver

Signed-off-by: Patrice Chotard <patrice.chotard@st.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
drivers/pinctrl/Kconfig
drivers/pinctrl/Makefile
drivers/pinctrl/pinctrl-sti.c [new file with mode: 0644]

index efcb4c0003a68935e777d3fcca4bb90cbc7ef4d0..0c832e187da0cffdf6eb83eff2f7a64180031cf1 100644 (file)
@@ -175,6 +175,16 @@ config PIC32_PINCTRL
          by a device tree node which contains both GPIO defintion and pin control
          functions.
 
+config PINCTRL_STI
+       bool "STMicroelectronics STi pin-control and pin-mux driver"
+       depends on DM && ARCH_STI
+       default y
+       help
+         Support pin multiplexing control on STMicrolectronics STi SoCs.
+         The driver is controlled by a device tree node which contains both
+         the GPIO definitions and pin control functions for each available multiplex
+         function.
+
 endif
 
 source "drivers/pinctrl/meson/Kconfig"
index 512112af649e1027ce1982d6038b388991e2a225..a2f810156b87ee85fd04ec703ea20741a1ae512a 100644 (file)
@@ -16,3 +16,4 @@ obj-$(CONFIG_PIC32_PINCTRL)   += pinctrl_pic32.o
 obj-$(CONFIG_PINCTRL_EXYNOS)   += exynos/
 obj-$(CONFIG_PINCTRL_MESON)    += meson/
 obj-$(CONFIG_PINCTRL_MVEBU)    += mvebu/
+obj-$(CONFIG_PINCTRL_STI)      += pinctrl-sti.o
diff --git a/drivers/pinctrl/pinctrl-sti.c b/drivers/pinctrl/pinctrl-sti.c
new file mode 100644 (file)
index 0000000..40341b4
--- /dev/null
@@ -0,0 +1,320 @@
+/*
+ * Pinctrl driver for STMicroelectronics STi SoCs
+ *
+ *  Copyright (c) 2017
+ *  Patrice Chotard <patrice.chotard@st.com>
+ *
+ * SPDX-License-Identifier:    GPL-2.0
+ */
+
+#include <common.h>
+#include <bitfield.h>
+#include <dm.h>
+#include <errno.h>
+#include <regmap.h>
+#include <syscon.h>
+#include <asm/io.h>
+#include <dm/pinctrl.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#define MAX_STI_PINCONF_ENTRIES                7
+/* Output enable */
+#define OE                     (1 << 27)
+/* Pull Up */
+#define PU                     (1 << 26)
+/* Open Drain */
+#define OD                     (1 << 25)
+
+/* User-frendly defines for Pin Direction */
+               /* oe = 0, pu = 0, od = 0 */
+#define IN                     (0)
+               /* oe = 0, pu = 1, od = 0 */
+#define IN_PU                  (PU)
+               /* oe = 1, pu = 0, od = 0 */
+#define OUT                    (OE)
+               /* oe = 1, pu = 1, od = 0 */
+#define OUT_PU                 (OE | PU)
+               /* oe = 1, pu = 0, od = 1 */
+#define BIDIR                  (OE | OD)
+               /* oe = 1, pu = 1, od = 1 */
+#define BIDIR_PU               (OE | PU | OD)
+
+struct sti_pinctrl_platdata {
+       struct regmap *regmap;
+};
+
+struct sti_pin_desc {
+       unsigned char bank;
+       unsigned char pin;
+       unsigned char alt;
+       int dir;
+};
+
+/*
+ * PIO alternative Function selector
+ */
+void sti_alternate_select(struct udevice *dev, struct sti_pin_desc *pin_desc)
+{
+       struct sti_pinctrl_platdata *plat = dev_get_platdata(dev);
+       unsigned long sysconf, *sysconfreg;
+       int alt = pin_desc->alt;
+       int bank = pin_desc->bank;
+       int pin = pin_desc->pin;
+
+       sysconfreg = (unsigned long *)plat->regmap->base;
+
+       switch (bank) {
+       case 0 ... 5:           /* in "SBC Bank" */
+               sysconfreg += bank;
+               break;
+       case 10 ... 20:         /* in "FRONT Bank" */
+               sysconfreg += bank - 10;
+               break;
+       case 30 ... 35:         /* in "REAR Bank" */
+               sysconfreg += bank - 30;
+               break;
+       case 40 ... 42:         /* in "FLASH Bank" */
+               sysconfreg += bank - 40;
+               break;
+       default:
+               BUG();
+               return;
+       }
+
+       sysconf = readl(sysconfreg);
+       sysconf = bitfield_replace(sysconf, pin * 4, 3, alt);
+       writel(sysconf, sysconfreg);
+}
+
+/* pin configuration */
+void sti_pin_configure(struct udevice *dev, struct sti_pin_desc *pin_desc)
+{
+       struct sti_pinctrl_platdata *plat = dev_get_platdata(dev);
+       int bit;
+       int oe = 0, pu = 0, od = 0;
+       unsigned long *sysconfreg;
+       int bank = pin_desc->bank;
+
+       sysconfreg = (unsigned long *)plat->regmap->base + 40;
+
+       /*
+        * NOTE: The PIO configuration for the PIO pins in the
+        * "FLASH Bank" are different from all the other banks!
+        * Specifically, the output-enable pin control register
+        * (SYS_CFG_3040) and the pull-up pin control register
+        * (SYS_CFG_3050), are both classed as being "reserved".
+        * Hence, we do not write to these registers to configure
+        * the OE and PU features for PIOs in this bank. However,
+        * the open-drain pin control register (SYS_CFG_3060)
+        * follows the style of the other banks, and so we can
+        * treat that register normally.
+        *
+        * Being pedantic, we should configure the PU and PD features
+        * in the "FLASH Bank" explicitly instead using the four
+        * SYS_CFG registers: 3080, 3081, 3085, and 3086. However, this
+        * would necessitate passing in the alternate function number
+        * to this function, and adding some horrible complexity here.
+        * Alternatively, we could just perform 4 32-bit "pokes" to
+        * these four SYS_CFG registers early in the initialization.
+        * In practice, these four SYS_CFG registers are correct
+        * after a reset, and U-Boot does not need to change them, so
+        * we (cheat and) rely on these registers being correct.
+        * WARNING: Please be aware of this (pragmatic) behaviour!
+        */
+       int flashss = 0;        /* bool: PIO in the Flash Sub-System ? */
+
+       switch (pin_desc->dir) {
+       case IN:
+               oe = 0; pu = 0; od = 0;
+               break;
+       case IN_PU:
+               oe = 0; pu = 1; od = 0;
+               break;
+       case OUT:
+               oe = 1; pu = 0; od = 0;
+               break;
+       case BIDIR:
+               oe = 1; pu = 0; od = 1;
+               break;
+       case BIDIR_PU:
+               oe = 1; pu = 1; od = 1;
+               break;
+
+       default:
+               error("%s invalid direction value: 0x%x\n",
+                     __func__, pin_desc->dir);
+               BUG();
+               break;
+       }
+
+       switch (bank) {
+       case 0 ... 5:           /* in "SBC Bank" */
+               sysconfreg += bank / 4;
+               break;
+       case 10 ... 20:         /* in "FRONT Bank" */
+               bank -= 10;
+               sysconfreg += bank / 4;
+               break;
+       case 30 ... 35:         /* in "REAR Bank" */
+               bank -= 30;
+               sysconfreg += bank / 4;
+               break;
+       case 40 ... 42:         /* in "FLASH Bank" */
+               bank -= 40;
+               sysconfreg += bank / 4;
+               flashss = 1;    /* pin is in the Flash Sub-System */
+               break;
+       default:
+               BUG();
+               return;
+       }
+
+       bit = ((bank * 8) + pin_desc->pin) % 32;
+
+       /*
+        * set the "Output Enable" pin control
+        * but, do nothing if in the flashSS
+        */
+       if (!flashss) {
+               if (oe)
+                       generic_set_bit(bit, sysconfreg);
+               else
+                       generic_clear_bit(bit, sysconfreg);
+       }
+
+       sysconfreg += 10;       /* skip to next set of syscfg registers */
+
+       /*
+        * set the "Pull Up" pin control
+        * but, do nothing if in the FlashSS
+        */
+
+       if (!flashss) {
+               if (pu)
+                       generic_set_bit(bit, sysconfreg);
+               else
+                       generic_clear_bit(bit, sysconfreg);
+       }
+
+       sysconfreg += 10;       /* skip to next set of syscfg registers */
+
+       /* set the "Open Drain Enable" pin control */
+       if (od)
+               generic_set_bit(bit, sysconfreg);
+       else
+               generic_clear_bit(bit, sysconfreg);
+}
+
+
+static int sti_pinctrl_set_state(struct udevice *dev, struct udevice *config)
+{
+       struct fdtdec_phandle_args args;
+       const void *blob = gd->fdt_blob;
+       const char *prop_name;
+       int node = dev_of_offset(config);
+       int property_offset, prop_len;
+       int pinconf_node, ret, count;
+       const char *bank_name;
+       u32 cells[MAX_STI_PINCONF_ENTRIES];
+
+       struct sti_pin_desc pin_desc;
+
+       /* go to next node "st,pins" which contains the pins configuration */
+       pinconf_node = fdt_subnode_offset(blob, node, "st,pins");
+
+       /*
+        * parse each pins configuration which looks like :
+        *      pin_name = <bank_phandle pin_nb alt dir rt_type rt_delay rt_clk>
+        */
+
+       fdt_for_each_property_offset(property_offset, blob, pinconf_node) {
+               fdt_getprop_by_offset(blob, property_offset, &prop_name,
+                                     &prop_len);
+
+               /* extract the bank of the pin description */
+               ret = fdtdec_parse_phandle_with_args(blob, pinconf_node,
+                                                    prop_name, "#gpio-cells",
+                                                    0, 0, &args);
+               if (ret < 0) {
+                       error("Can't get the gpio bank phandle: %d\n", ret);
+                       return ret;
+               }
+
+               bank_name = fdt_getprop(blob, args.node, "st,bank-name",
+                                       &count);
+               if (count < 0) {
+                       error("Can't find bank-name property %d\n", count);
+                       return -EINVAL;
+               }
+
+               pin_desc.bank = trailing_strtoln(bank_name, NULL);
+
+               count = fdtdec_get_int_array_count(blob, pinconf_node,
+                                                  prop_name, cells,
+                                                  ARRAY_SIZE(cells));
+               if (count < 0) {
+                       error("Bad pin configuration array %d\n", count);
+                       return -EINVAL;
+               }
+
+               if (count > MAX_STI_PINCONF_ENTRIES) {
+                       error("Unsupported pinconf array count %d\n", count);
+                       return -EINVAL;
+               }
+
+               pin_desc.pin = cells[1];
+               pin_desc.alt = cells[2];
+               pin_desc.dir = cells[3];
+
+               sti_alternate_select(dev, &pin_desc);
+               sti_pin_configure(dev, &pin_desc);
+       };
+
+       return 0;
+}
+
+static int sti_pinctrl_probe(struct udevice *dev)
+{
+       struct sti_pinctrl_platdata *plat = dev_get_platdata(dev);
+       struct udevice *syscon;
+       int err;
+
+       /* get corresponding syscon phandle */
+       err = uclass_get_device_by_phandle(UCLASS_SYSCON, dev,
+                                          "st,syscfg", &syscon);
+       if (err) {
+               error("unable to find syscon device\n");
+               return err;
+       }
+
+       plat->regmap = syscon_get_regmap(syscon);
+       if (!plat->regmap) {
+               error("unable to find regmap\n");
+               return -ENODEV;
+       }
+
+       return 0;
+}
+
+static const struct udevice_id sti_pinctrl_ids[] = {
+       { .compatible = "st,stih407-sbc-pinctrl" },
+       { .compatible = "st,stih407-front-pinctrl" },
+       { .compatible = "st,stih407-rear-pinctrl" },
+       { .compatible = "st,stih407-flash-pinctrl" },
+       { }
+};
+
+const struct pinctrl_ops sti_pinctrl_ops = {
+       .set_state = sti_pinctrl_set_state,
+};
+
+U_BOOT_DRIVER(pinctrl_sti) = {
+       .name = "pinctrl_sti",
+       .id = UCLASS_PINCTRL,
+       .of_match = sti_pinctrl_ids,
+       .ops = &sti_pinctrl_ops,
+       .probe = sti_pinctrl_probe,
+       .platdata_auto_alloc_size = sizeof(struct sti_pinctrl_platdata),
+       .ops = &sti_pinctrl_ops,
+};