The XWAY family allows to extend the number of gpios by using shift registers or latches. This patch adds the 2 drivers needed for this. The extended gpios are output only.
Signed-off-by: John Crispin <blogic@xxxxxxxxxxx>
Signed-off-by: Ralph Hempel <ralph.hempel@xxxxxxxxxx>
Cc: linux-mips@xxxxxxxxxxxxxx
---
Added in V2
Changes in V3
* whitespace
* change __iomem void to void __iomem
* multiline comments
* use pr_* macros instead of printk
Changes in V4
* whitespace fixes
* properly insert and request all memory ranges
arch/mips/lantiq/xway/Makefile | 2 +-
arch/mips/lantiq/xway/gpio_ebu.c | 130 +++++++++++++++++++++++++++++++
arch/mips/lantiq/xway/gpio_stp.c | 160 ++++++++++++++++++++++++++++++++++++++
3 files changed, 291 insertions(+), 1 deletions(-)
create mode 100644 arch/mips/lantiq/xway/gpio_ebu.c
create mode 100644 arch/mips/lantiq/xway/gpio_stp.c
diff --git a/arch/mips/lantiq/xway/Makefile b/arch/mips/lantiq/xway/Makefile
index 08dcc10..a021def 100644
--- a/arch/mips/lantiq/xway/Makefile
+++ b/arch/mips/lantiq/xway/Makefile
@@ -1,4 +1,4 @@
-obj-y := pmu.o ebu.o reset.o gpio.o devices.o
+obj-y := pmu.o ebu.o reset.o gpio.o gpio_stp.o gpio_ebu.o devices.o
obj-$(CONFIG_SOC_XWAY) += clk-xway.o prom-xway.o
obj-$(CONFIG_SOC_AMAZON_SE) += clk-ase.o prom-ase.o
diff --git a/arch/mips/lantiq/xway/gpio_ebu.c b/arch/mips/lantiq/xway/gpio_ebu.c
new file mode 100644
index 0000000..8ebc1a4
--- /dev/null
+++ b/arch/mips/lantiq/xway/gpio_ebu.c
@@ -0,0 +1,130 @@
+/*
+ * 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) 2010 John Crispin <blogic@xxxxxxxxxxx>
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/platform_device.h>
+#include <linux/mutex.h>
+#include <linux/gpio.h>
+#include <linux/io.h>
+
+#include <lantiq_soc.h>
+
+/* By attaching hardware latches to the EBU it is possible to create output
+ * only gpios. This driver configures a special memory address, which when
+ * written to outputs 16 bit to the latches.
+ */
+
+#define LTQ_EBU_BUSCON 0x1e7ff /* 16 bit access, slowest timing */
+#define LTQ_EBU_WP 0x80000000 /* write protect bit */
+
+/* we keep a shadow value of the last value written to the ebu */
+static int ltq_ebu_gpio_shadow = 0x0;
+static void __iomem *ltq_ebu_gpio_membase;
+
+static void
+ltq_ebu_apply(void)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&ebu_lock, flags);
+ ltq_ebu_w32(LTQ_EBU_BUSCON, LTQ_EBU_BUSCON1);
+ *((__u16 *)ltq_ebu_gpio_membase) = ltq_ebu_gpio_shadow;
+ ltq_ebu_w32(LTQ_EBU_BUSCON | LTQ_EBU_WP, LTQ_EBU_BUSCON1);
+ spin_unlock_irqrestore(&ebu_lock, flags);
+}
+
+static void
+ltq_ebu_set(struct gpio_chip *chip, unsigned offset, int value)
+{
+ if (value)
+ ltq_ebu_gpio_shadow |= (1 << offset);
+ else
+ ltq_ebu_gpio_shadow &= ~(1 << offset);
+ ltq_ebu_apply();
+}
+
+static int
+ltq_ebu_direction_output(struct gpio_chip *chip, unsigned offset, int value)
+{
+ ltq_ebu_set(chip, offset, value);
+ return 0;
+}
+
+static struct gpio_chip
+ltq_ebu_chip = {
+ .label = "ltq_ebu",
+ .direction_output = ltq_ebu_direction_output,
+ .set = ltq_ebu_set,
+ .base = 72,
+ .ngpio = 16,
+ .can_sleep = 1,
+ .owner = THIS_MODULE,
+};
+
+static int
+ltq_ebu_probe(struct platform_device *pdev)
+{
+ int ret = 0;
+ struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+
+ if (!res) {
+ dev_err(&pdev->dev, "failed to get memory resource\n");
+ 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 memory resource\n");
+ return -EBUSY;
+ }
+
+ ltq_ebu_gpio_membase = devm_ioremap_nocache(&pdev->dev, res->start,
+ resource_size(res));
+ if (!ltq_ebu_gpio_membase) {
+ dev_err(&pdev->dev, "Failed to ioremap mem region\n");
+ return -ENOMEM;
+ }
+
+ /* grab the default shadow value passed form the platform code */
+ ltq_ebu_gpio_shadow = (unsigned int) pdev->dev.platform_data;
+
+ /* tell the ebu controller which memory address we will be using */
+ ltq_ebu_w32(pdev->resource->start | 0x1, LTQ_EBU_ADDRSEL1);
+
+ /* write protect the region */
+ ltq_ebu_w32(LTQ_EBU_BUSCON | LTQ_EBU_WP, LTQ_EBU_BUSCON1);
+
+ ret = gpiochip_add(<q_ebu_chip);
+ if (!ret)
+ ltq_ebu_apply();
+ return ret;
+}
+
+static struct platform_driver
+ltq_ebu_driver = {
+ .probe = ltq_ebu_probe,
+ .driver = {
+ .name = "ltq_ebu",
+ .owner = THIS_MODULE,
+ },
+};
+
+static int __init
+ltq_ebu_init(void)
+{
+ int ret = platform_driver_register(<q_ebu_driver);
+
+ if (ret)
+ pr_info("ltq_ebu : Error registering platfom driver!");
+ return ret;
+}
+
+postcore_initcall(ltq_ebu_init);
diff --git a/arch/mips/lantiq/xway/gpio_stp.c b/arch/mips/lantiq/xway/gpio_stp.c
new file mode 100644
index 0000000..4bd7c3e
--- /dev/null
+++ b/arch/mips/lantiq/xway/gpio_stp.c
@@ -0,0 +1,160 @@
+/*
+ * 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/module.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)
+{
+ /* the 3 pins used to control the external stp */
+ ltq_gpio_request(4, 1, 0, 1, "stp-st");
+ ltq_gpio_request(5, 1, 0, 1, "stp-d");
+ ltq_gpio_request(6, 1, 0, 1, "stp-sh");
+
+ /* 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 __init
+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);
--
1.7.2.3
