Implements OF support and moves the driver from arch/mips/lantiq/xway/ to the
gpio subsystem.
The Serial To Parallel (STP) is found on MIPS based Lantiq socs. It is a
peripheral controller used to drive external shift register cascades. At most
3 groups of 8 bits can be driven. The hardware is able to allow the DSL modem
to drive the 2 LSBs of the cascade automatically. The driver currently only
supports output functionality. Patches for the input feature found on newer
generations of the soc will be provided in a later series.
Signed-off-by: John Crispin <blogic@xxxxxxxxxxx>
Cc: Grant Likely <grant.likely@xxxxxxxxxxxx>
Cc: linux-kernel@xxxxxxxxxxxxxxx
---
This patch is part of a series moving the mips/lantiq target to OF and clkdev
support. The patch, once Acked, should go upstream via Ralf's MIPS tree.
arch/mips/lantiq/xway/Makefile | 2 +-
arch/mips/lantiq/xway/gpio_stp.c | 152 -------------------
drivers/gpio/Kconfig | 10 ++
drivers/gpio/Makefile | 1 +
drivers/gpio/gpio-stp-xway.c | 300 ++++++++++++++++++++++++++++++++++++++
5 files changed, 312 insertions(+), 153 deletions(-)
delete mode 100644 arch/mips/lantiq/xway/gpio_stp.c
create mode 100644 drivers/gpio/gpio-stp-xway.c
diff --git a/arch/mips/lantiq/xway/Makefile b/arch/mips/lantiq/xway/Makefile
index edef6c5..d0a0c96 100644
--- a/arch/mips/lantiq/xway/Makefile
+++ b/arch/mips/lantiq/xway/Makefile
@@ -1 +1 @@
-obj-y := prom.o sysctrl.o clk.o reset.o gpio.o gpio_stp.o gpio_ebu.o dma.o
+obj-y := prom.o sysctrl.o clk.o reset.o gpio.o gpio_ebu.o dma.o
diff --git a/arch/mips/lantiq/xway/gpio_stp.c b/arch/mips/lantiq/xway/gpio_stp.c
deleted file mode 100644
index d674f1b..0000000
--- a/arch/mips/lantiq/xway/gpio_stp.c
+++ /dev/null
@@ -1,152 +0,0 @@
-/*
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License version 2 as published
- * by the Free Software Foundation.
- *
- * Copyright (C) 2007 John Crispin <blogic@xxxxxxxxxxx>
- *
- */
-
-#include <linux/slab.h>
-#include <linux/init.h>
-#include <linux/export.h>
-#include <linux/types.h>
-#include <linux/platform_device.h>
-#include <linux/mutex.h>
-#include <linux/io.h>
-#include <linux/gpio.h>
-
-#include <lantiq_soc.h>
-
-#define LTQ_STP_CON0 0x00
-#define LTQ_STP_CON1 0x04
-#define LTQ_STP_CPU0 0x08
-#define LTQ_STP_CPU1 0x0C
-#define LTQ_STP_AR 0x10
-
-#define LTQ_STP_CON_SWU (1 << 31)
-#define LTQ_STP_2HZ 0
-#define LTQ_STP_4HZ (1 << 23)
-#define LTQ_STP_8HZ (2 << 23)
-#define LTQ_STP_10HZ (3 << 23)
-#define LTQ_STP_SPEED_MASK (0xf << 23)
-#define LTQ_STP_UPD_FPI (1 << 31)
-#define LTQ_STP_UPD_MASK (3 << 30)
-#define LTQ_STP_ADSL_SRC (3 << 24)
-
-#define LTQ_STP_GROUP0 (1 << 0)
-
-#define LTQ_STP_RISING 0
-#define LTQ_STP_FALLING (1 << 26)
-#define LTQ_STP_EDGE_MASK (1 << 26)
-
-#define ltq_stp_r32(reg) __raw_readl(ltq_stp_membase + reg)
-#define ltq_stp_w32(val, reg) __raw_writel(val, ltq_stp_membase + reg)
-#define ltq_stp_w32_mask(clear, set, reg) \
- ltq_w32((ltq_r32(ltq_stp_membase + reg) & ~(clear)) | (set), \
- ltq_stp_membase + (reg))
-
-static int ltq_stp_shadow = 0xffff;
-static void __iomem *ltq_stp_membase;
-
-static void ltq_stp_set(struct gpio_chip *chip, unsigned offset, int value)
-{
- if (value)
- ltq_stp_shadow |= (1 << offset);
- else
- ltq_stp_shadow &= ~(1 << offset);
- ltq_stp_w32(ltq_stp_shadow, LTQ_STP_CPU0);
-}
-
-static int ltq_stp_direction_output(struct gpio_chip *chip, unsigned offset,
- int value)
-{
- ltq_stp_set(chip, offset, value);
-
- return 0;
-}
-
-static struct gpio_chip ltq_stp_chip = {
- .label = "ltq_stp",
- .direction_output = ltq_stp_direction_output,
- .set = ltq_stp_set,
- .base = 48,
- .ngpio = 24,
- .can_sleep = 1,
- .owner = THIS_MODULE,
-};
-
-static int ltq_stp_hw_init(void)
-{
- /* sane defaults */
- ltq_stp_w32(0, LTQ_STP_AR);
- ltq_stp_w32(0, LTQ_STP_CPU0);
- ltq_stp_w32(0, LTQ_STP_CPU1);
- ltq_stp_w32(LTQ_STP_CON_SWU, LTQ_STP_CON0);
- ltq_stp_w32(0, LTQ_STP_CON1);
-
- /* rising or falling edge */
- ltq_stp_w32_mask(LTQ_STP_EDGE_MASK, LTQ_STP_FALLING, LTQ_STP_CON0);
-
- /* per default stp 15-0 are set */
- ltq_stp_w32_mask(0, LTQ_STP_GROUP0, LTQ_STP_CON1);
-
- /* stp are update periodically by the FPI bus */
- ltq_stp_w32_mask(LTQ_STP_UPD_MASK, LTQ_STP_UPD_FPI, LTQ_STP_CON1);
-
- /* set stp update speed */
- ltq_stp_w32_mask(LTQ_STP_SPEED_MASK, LTQ_STP_8HZ, LTQ_STP_CON1);
-
- /* tell the hardware that pin (led) 0 and 1 are controlled
- * by the dsl arc
- */
- ltq_stp_w32_mask(0, LTQ_STP_ADSL_SRC, LTQ_STP_CON0);
-
- ltq_pmu_enable(PMU_LED);
- return 0;
-}
-
-static int __devinit ltq_stp_probe(struct platform_device *pdev)
-{
- struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- int ret = 0;
-
- if (!res)
- return -ENOENT;
- res = devm_request_mem_region(&pdev->dev, res->start,
- resource_size(res), dev_name(&pdev->dev));
- if (!res) {
- dev_err(&pdev->dev, "failed to request STP memory\n");
- return -EBUSY;
- }
- ltq_stp_membase = devm_ioremap_nocache(&pdev->dev, res->start,
- resource_size(res));
- if (!ltq_stp_membase) {
- dev_err(&pdev->dev, "failed to remap STP memory\n");
- return -ENOMEM;
- }
- ret = gpiochip_add(<q_stp_chip);
- if (!ret)
- ret = ltq_stp_hw_init();
-
- return ret;
-}
-
-static struct platform_driver ltq_stp_driver = {
- .probe = ltq_stp_probe,
- .driver = {
- .name = "ltq_stp",
- .owner = THIS_MODULE,
- },
-};
-
-int __init ltq_stp_init(void)
-{
- int ret = platform_driver_register(<q_stp_driver);
-
- if (ret)
- pr_info("ltq_stp: error registering platfom driver");
- return ret;
-}
-
-postcore_initcall(ltq_stp_init);
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index e03653d..4875071 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -306,6 +306,16 @@ config GPIO_STMPE
This enables support for the GPIOs found on the STMPE I/O
Expanders.
+config GPIO_STP_XWAY
+ bool "XWAY STP GPIOs"
+ depends on SOC_XWAY
+ help
+ This enables support for the Serial To Parallel (STP) unit found on
+ XWAY SoC. The STP allows the SoC to drive a shift registers cascade,
+ that can be up to 24 bit. This peripheral is aimed at driving leds.
+ Some of the gpios/leds can be auto updated by the soc with dsl and
+ phy status.
+
config GPIO_TC3589X
bool "TC3589X GPIOs"
depends on MFD_TC3589X
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 007f54b..6447841 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -49,6 +49,7 @@ obj-$(CONFIG_ARCH_SA1100) += gpio-sa1100.o
obj-$(CONFIG_GPIO_SCH) += gpio-sch.o
obj-$(CONFIG_GPIO_SODAVILLE) += gpio-sodaville.o
obj-$(CONFIG_GPIO_STMPE) += gpio-stmpe.o
+obj-$(CONFIG_GPIO_STP_XWAY) += gpio-stp-xway.o
obj-$(CONFIG_GPIO_SX150X) += gpio-sx150x.o
obj-$(CONFIG_GPIO_TC3589X) += gpio-tc3589x.o
obj-$(CONFIG_ARCH_TEGRA) += gpio-tegra.o
diff --git a/drivers/gpio/gpio-stp-xway.c b/drivers/gpio/gpio-stp-xway.c
new file mode 100644
index 0000000..9b53adf
--- /dev/null
+++ b/drivers/gpio/gpio-stp-xway.c
@@ -0,0 +1,300 @@
+/*
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ *
+ * Copyright (C) 2012 John Crispin <blogic@xxxxxxxxxxx>
+ *
+ */
+
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/of_platform.h>
+#include <linux/mutex.h>
+#include <linux/io.h>
+#include <linux/of_gpio.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+
+#include <lantiq_soc.h>
+
+/*
+ * The Serial To Parallel (STP) is found on MIPS based Lantiq socs. It is a
+ * peripheral controller used to drive external shift register cascades. At most
+ * 3 groups of 8 bits can be driven. The hardware is able to allow the DSL modem
+ * to drive the 2 LSBs of the cascade automatically.
+ */
+
+/* control register 0 */
+#define XWAY_STP_CON0 0x00
+/* control register 1 */
+#define XWAY_STP_CON1 0x04
+/* data register 0 */
+#define XWAY_STP_CPU0 0x08
+/* data register 1 */
+#define XWAY_STP_CPU1 0x0C
+/* access register */
+#define XWAY_STP_AR 0x10
+
+/* software or hardware update select bit */
+#define XWAY_STP_CON_SWU BIT(31)
+
+/* automatic update rates */
+#define XWAY_STP_2HZ 0
+#define XWAY_STP_4HZ BIT(23)
+#define XWAY_STP_8HZ BIT(24)
+#define XWAY_STP_10HZ (BIT(24) | BIT(23))
+#define XWAY_STP_SPEED_MASK (0xf << 23)
+
+/* clock source for automatic update */
+#define XWAY_STP_UPD_FPI BIT(31)
+#define XWAY_STP_UPD_MASK (BIT(31) | BIT(30))
+
+/* let the adsl core drive the 2 LSBs */
+#define XWAY_STP_ADSL_SHIFT 24
+#define XWAY_STP_ADSL_MASK 0x3
+
+/* 2 groups of 3 bits can be driven by the phys */
+#define XWAY_STP_PHY_MASK 0x3
+#define XWAY_STP_PHY1_SHIFT 27
+#define XWAY_STP_PHY2_SHIFT 15
+
+/* STP has 3 groups of 8 bits */
+#define XWAY_STP_GROUP0 BIT(0)
+#define XWAY_STP_GROUP1 BIT(1)
+#define XWAY_STP_GROUP2 BIT(2)
+#define XWAY_STP_GROUP_MASK (0x7)
+
+/* Edge configuration bits */
+#define XWAY_STP_FALLING BIT(26)
+#define XWAY_STP_EDGE_MASK BIT(26)
+
+#define xway_stp_r32(m, reg) __raw_readl(m + reg)
+#define xway_stp_w32(m, val, reg) __raw_writel(val, m + reg)
+#define xway_stp_w32_mask(m, clear, set, reg) \
+ ltq_w32((ltq_r32(m + reg) & ~(clear)) | (set), \
+ m + reg)
+
+struct xway_stp {
+ struct gpio_chip gc;
+ void __iomem *virt;
+ u32 edge; /* rising or falling edge triggered shift register */
+ u16 shadow; /* shadow the shift registers state */
+ u8 groups; /* we can drive 1-3 groups of 8bit each */
+ u8 dsl; /* the 2 LSBs can be driven by the dsl core */
+ u8 phy1; /* 3 bits can be driven by phy1 */
+ u8 phy2; /* 3 bits can be driven by phy2 */
+ u8 reserved; /* mask out the hw driven bits in gpio_request */
+};
+
+/*
+ * xway_stp_set - gpio_chip->set - set gpios.
+ * @gc: Pointer to gpio_chip device structure.
+ * @gpio: GPIO signal number.
+ * @val: Value to be written to specified signal.
+ *
+ * Set the shadow value and call ltq_ebu_apply.
+ */
+static void xway_stp_set(struct gpio_chip *gc, unsigned gpio, int val)
+{
+ struct xway_stp *chip =
+ container_of(gc, struct xway_stp, gc);
+
+ if (val)
+ chip->shadow |= BIT(gpio);
+ else
+ chip->shadow &= ~BIT(gpio);
+ xway_stp_w32(chip->virt, chip->shadow, XWAY_STP_CPU0);
+ xway_stp_w32_mask(chip->virt, 0, XWAY_STP_CON_SWU, XWAY_STP_CON0);
+}
+
+/*
+ * xway_stp_dir_out - gpio_chip->dir_out - set gpio direction.
+ * @gc: Pointer to gpio_chip device structure.
+ * @gpio: GPIO signal number.
+ * @val: Value to be written to specified signal.
+ *
+ * Same as xway_stp_set, always returns 0.
+ */
+static int xway_stp_dir_out(struct gpio_chip *gc, unsigned gpio, int val)
+{
+ xway_stp_set(gc, gpio, val);
+
+ return 0;
+}
+
+/*
+ * xway_stp_request - gpio_chip->request
+ * @gc: Pointer to gpio_chip device structure.
+ * @gpio: GPIO signal number.
+ *
+ * We mask out the HW driven pins
+ */
+static int xway_stp_request(struct gpio_chip *gc, unsigned gpio)
+{
+ struct xway_stp *chip =
+ container_of(gc, struct xway_stp, gc);
+
+ if ((gpio < 8) && (chip->reserved & BIT(gpio))) {
+ dev_err(gc->dev, "GPIO %d is driven by hardware\n", gpio);
+ return -ENODEV;
+ }
+
+ return 0;
+}
+
+/*
+ * xway_stp_hw_init - Configure the STP unit and enable the clock gate
+ * @virt: pointer to the remapped register range
+ */
+static int xway_stp_hw_init(struct xway_stp *chip)
+{
+ /* sane defaults */
+ xway_stp_w32(chip->virt, 0, XWAY_STP_AR);
+ xway_stp_w32(chip->virt, 0, XWAY_STP_CPU0);
+ xway_stp_w32(chip->virt, 0, XWAY_STP_CPU1);
+ xway_stp_w32(chip->virt, XWAY_STP_CON_SWU, XWAY_STP_CON0);
+ xway_stp_w32(chip->virt, 0, XWAY_STP_CON1);
+
+ /* apply edge trigger settings for the shift register */
+ xway_stp_w32_mask(chip->virt, XWAY_STP_EDGE_MASK,
+ chip->edge, XWAY_STP_CON0);
+
+ /* apply led group settings */
+ xway_stp_w32_mask(chip->virt, XWAY_STP_GROUP_MASK,
+ chip->groups, XWAY_STP_CON1);
+
+ /* tell the hardware which pins are controlled by the dsl modem */
+ xway_stp_w32_mask(chip->virt,
+ XWAY_STP_ADSL_MASK << XWAY_STP_ADSL_SHIFT,
+ chip->dsl << XWAY_STP_ADSL_SHIFT,
+ XWAY_STP_CON0);
+
+ /* tell the hardware which pins are controlled by the phys */
+ xway_stp_w32_mask(chip->virt,
+ XWAY_STP_PHY_MASK << XWAY_STP_PHY1_SHIFT,
+ chip->phy1 << XWAY_STP_PHY1_SHIFT,
+ XWAY_STP_CON0);
+ xway_stp_w32_mask(chip->virt,
+ XWAY_STP_PHY_MASK << XWAY_STP_PHY2_SHIFT,
+ chip->phy2 << XWAY_STP_PHY2_SHIFT,
+ XWAY_STP_CON1);
+
+ /* mask out the hw driven bits in gpio_request */
+ chip->reserved = (chip->phy2 << 5) | (chip->phy1 << 2) | chip->dsl;
+
+ /*
+ * if we have pins that are driven by hw, we need to tell the stp what
+ * clock to use as a timer.
+ */
+ if (chip->reserved)
+ xway_stp_w32_mask(chip->virt, XWAY_STP_UPD_MASK,
+ XWAY_STP_UPD_FPI, XWAY_STP_CON1);
+
+ return 0;
+}
+
+static int __devinit xway_stp_probe(struct platform_device *pdev)
+{
+ struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ const __be32 *shadow, *groups, *dsl, *phy;
+ struct xway_stp *chip;
+ struct clk *clk;
+ int ret = 0;
+
+ if (!res) {
+ dev_err(&pdev->dev, "failed to request STP resource\n");
+ return -ENOENT;
+ }
+
+ chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
+ if (!chip)
+ return -ENOMEM;
+
+ chip->virt = devm_request_and_ioremap(&pdev->dev, res);
+ if (!chip->virt) {
+ dev_err(&pdev->dev, "failed to remap STP memory\n");
+ return -ENOMEM;
+ }
+ chip->gc.dev = &pdev->dev;
+ chip->gc.label = "stp-xway";
+ chip->gc.direction_output = xway_stp_dir_out;
+ chip->gc.set = xway_stp_set;
+ chip->gc.request = xway_stp_request;
+ chip->gc.base = -1;
+ chip->gc.owner = THIS_MODULE;
+
+ /* store the shadow value if one was passed by the devicetree */
+ shadow = of_get_property(pdev->dev.of_node, "lantiq,shadow", NULL);
+ if (shadow)
+ chip->shadow = *shadow;
+
+ /* find out which gpio groups should be enabled */
+ groups = of_get_property(pdev->dev.of_node, "lantiq,groups", NULL);
+ if (groups)
+ chip->groups = *groups & XWAY_STP_GROUP_MASK;
+ else
+ chip->groups = XWAY_STP_GROUP0;
+ chip->gc.ngpio = fls(chip->groups) * 8;
+
+ /* find out which gpios are controlled by the dsl core */
+ dsl = of_get_property(pdev->dev.of_node, "lantiq,dsl", NULL);
+ if (dsl)
+ chip->dsl = *dsl & XWAY_STP_ADSL_MASK;
+
+ /* find out which gpios are controlled by the phys */
+ if (of_machine_is_compatible("lantiq,ar9") ||
+ of_machine_is_compatible("lantiq,gr9") ||
+ of_machine_is_compatible("lantiq,vr9")) {
+ phy = of_get_property(pdev->dev.of_node, "lantiq,phy1", NULL);
+ if (phy)
+ chip->phy1 = *phy & XWAY_STP_PHY_MASK;
+ phy = of_get_property(pdev->dev.of_node, "lantiq,phy2", NULL);
+ if (phy)
+ chip->phy2 = *phy & XWAY_STP_PHY_MASK;
+ }
+
+ /* check which edge trigger we should use, default to a falling edge */
+ if (!of_find_property(pdev->dev.of_node, "lantiq,rising", NULL))
+ chip->edge = XWAY_STP_FALLING;
+
+ clk = clk_get(&pdev->dev, NULL);
+ if (IS_ERR(clk)) {
+ dev_err(&pdev->dev, "Failed to get clock\n");
+ return PTR_ERR(clk);
+ }
+ clk_enable(clk);
+
+ ret = xway_stp_hw_init(chip);
+ if (!ret)
+ ret = gpiochip_add(&chip->gc);
+
+ if (!ret)
+ dev_info(&pdev->dev, "Init done\n");
+
+ return ret;
+}
+
+static const struct of_device_id xway_stp_match[] = {
+ { .compatible = "lantiq,gpio-stp-xway" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, xway_stp_match);
+
+static struct platform_driver xway_stp_driver = {
+ .probe = xway_stp_probe,
+ .driver = {
+ .name = "gpio-stp-xway",
+ .owner = THIS_MODULE,
+ .of_match_table = xway_stp_match,
+ },
+};
+
+int __init xway_stp_init(void)
+{
+ return platform_driver_register(&xway_stp_driver);
+}
+
+subsys_initcall(xway_stp_init);
--
1.7.9.1
