[ARM] 4964/1: htc-pasic3: MFD driver for PASIC3 LED control + DS1WM chip

This driver will provide registers, clocks and GPIOs of
the HTC PASIC3 (AIC3) and PASIC2 (AIC2) chips to the
ds1wm and leds-pasic3 drivers.

Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 265 insertions, 0 deletions

diff --git a/drivers/mfd/htc-pasic3.c b/drivers/mfd/htc-pasic3.c
new file mode 100644
index 000000000000..af66f4f28300
--- /dev/null
+++ b/drivers/mfd/htc-pasic3.c
@@ -0,0 +1,265 @@
+/*
+ * Core driver for HTC PASIC3 LED/DS1WM chip.
+ *
+ * Copyright (C) 2006 Philipp Zabel <philipp.zabel@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+
+#include <linux/ds1wm.h>
+#include <linux/gpio.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/mfd/htc-pasic3.h>
+
+#include <asm/arch/pxa-regs.h>
+
+struct pasic3_data {
+        void __iomem *mapping;
+        unsigned int bus_shift;
+        struct platform_device *ds1wm_pdev;
+        struct platform_device *led_pdev;
+};
+
+#define REG_ADDR  5
+#define REG_DATA  6
+#define NUM_REGS  7
+
+#define READ_MODE 0x80
+
+/*
+ * write to a secondary register on the PASIC3
+ */
+void pasic3_write_register(struct device *dev, u32 reg, u8 val)
+{
+        struct pasic3_data *asic = dev->driver_data;
+        int bus_shift = asic->bus_shift;
+        void __iomem *addr = asic->mapping + (REG_ADDR << bus_shift);
+        void __iomem *data = asic->mapping + (REG_DATA << bus_shift);
+
+        __raw_writeb(~READ_MODE & reg, addr);
+        __raw_writeb(val, data);
+}
+EXPORT_SYMBOL(pasic3_write_register); /* for leds-pasic3 */
+
+/*
+ * read from a secondary register on the PASIC3
+ */
+u8 pasic3_read_register(struct device *dev, u32 reg)
+{
+        struct pasic3_data *asic = dev->driver_data;
+        int bus_shift = asic->bus_shift;
+        void __iomem *addr = asic->mapping + (REG_ADDR << bus_shift);
+        void __iomem *data = asic->mapping + (REG_DATA << bus_shift);
+
+        __raw_writeb(READ_MODE | reg, addr);
+        return __raw_readb(data);
+}
+EXPORT_SYMBOL(pasic3_read_register); /* for leds-pasic3 */
+
+/*
+ * LEDs
+ */
+
+static int led_device_add(struct device *pasic3_dev,
+                                const struct pasic3_leds_machinfo *pdata)
+{
+        struct pasic3_data *asic = pasic3_dev->driver_data;
+        struct platform_device *pdev;
+        int ret;
+
+        pdev = platform_device_alloc("pasic3-led", -1);
+        if (!pdev) {
+                dev_dbg(pasic3_dev, "failed to allocate LED platform device\n");
+                return -ENOMEM;
+        }
+
+        ret = platform_device_add_data(pdev, pdata,
+                                        sizeof(struct pasic3_leds_machinfo));
+        if (ret < 0) {
+                dev_dbg(pasic3_dev, "failed to add LED platform data\n");
+                goto exit_pdev_put;
+        }
+
+        pdev->dev.parent = pasic3_dev;
+        ret = platform_device_add(pdev);
+        if (ret < 0) {
+                dev_dbg(pasic3_dev, "failed to add LED platform device\n");
+                goto exit_pdev_put;
+        }
+
+        asic->led_pdev = pdev;
+        return 0;
+
+exit_pdev_put:
+        platform_device_put(pdev);
+        return ret;
+}
+
+/*
+ * DS1WM
+ */
+
+static void ds1wm_enable(struct platform_device *pdev)
+{
+        struct device *dev = pdev->dev.parent;
+        int c;
+
+        c = pasic3_read_register(dev, 0x28);
+        pasic3_write_register(dev, 0x28, c & 0x7f);
+
+        dev_dbg(dev, "DS1WM OWM_EN low (active) %02x\n", c & 0x7f);
+}
+
+static void ds1wm_disable(struct platform_device *pdev)
+{
+        struct device *dev = pdev->dev.parent;
+        int c;
+
+        c = pasic3_read_register(dev, 0x28);
+        pasic3_write_register(dev, 0x28, c | 0x80);
+
+        dev_dbg(dev, "DS1WM OWM_EN high (inactive) %02x\n", c | 0x80);
+}
+
+static struct ds1wm_platform_data ds1wm_pdata = {
+        .bus_shift = 2,
+        .enable    = ds1wm_enable,
+        .disable   = ds1wm_disable,
+};
+
+static int ds1wm_device_add(struct device *pasic3_dev, int bus_shift)
+{
+        struct pasic3_data *asic = pasic3_dev->driver_data;
+        struct platform_device *pdev;
+        int ret;
+
+        pdev = platform_device_alloc("ds1wm", -1);
+        if (!pdev) {
+                dev_dbg(pasic3_dev, "failed to allocate DS1WM platform device\n");
+                return -ENOMEM;
+        }
+
+        ret = platform_device_add_resources(pdev, pdev->resource,
+                                                pdev->num_resources);
+        if (ret < 0) {
+                dev_dbg(pasic3_dev, "failed to add DS1WM resources\n");
+                goto exit_pdev_put;
+        }
+
+        ds1wm_pdata.bus_shift = asic->bus_shift;
+        ret = platform_device_add_data(pdev, &ds1wm_pdata,
+                                        sizeof(struct ds1wm_platform_data));
+        if (ret < 0) {
+                dev_dbg(pasic3_dev, "failed to add DS1WM platform data\n");
+                goto exit_pdev_put;
+        }
+
+        pdev->dev.parent = pasic3_dev;
+        ret = platform_device_add(pdev);
+        if (ret < 0) {
+                dev_dbg(pasic3_dev, "failed to add DS1WM platform device\n");
+                goto exit_pdev_put;
+        }
+
+        asic->ds1wm_pdev = pdev;
+        return 0;
+
+exit_pdev_put:
+        platform_device_put(pdev);
+        return ret;
+}
+
+static int __init pasic3_probe(struct platform_device *pdev)
+{
+        struct pasic3_platform_data *pdata = pdev->dev.platform_data;
+        struct device *dev = &pdev->dev;
+        struct pasic3_data *asic;
+        struct resource *r;
+        int ret;
+
+        r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+        if (!r)
+                return -ENXIO;
+
+        if (!request_mem_region(r->start, r->end - r->start + 1, "pasic3"))
+                return -EBUSY;
+
+        asic = kzalloc(sizeof(struct pasic3_data), GFP_KERNEL);
+        if (!asic)
+                return -ENOMEM;
+
+        platform_set_drvdata(pdev, asic);
+
+        if (pdata && pdata->bus_shift)
+                asic->bus_shift = pdata->bus_shift;
+        else
+                asic->bus_shift = 2;
+
+        asic->mapping = ioremap(r->start, r->end - r->start + 1);
+        if (!asic->mapping) {
+                dev_err(dev, "couldn't ioremap PASIC3\n");
+                kfree(asic);
+                return -ENOMEM;
+        }
+
+        ret = ds1wm_device_add(dev, asic->bus_shift);
+        if (ret < 0)
+                dev_warn(dev, "failed to register DS1WM\n");
+
+        if (pdata->led_pdata) {
+                ret = led_device_add(dev, pdata->led_pdata);
+                if (ret < 0)
+                        dev_warn(dev, "failed to register LED device\n");
+        }
+
+        return 0;
+}
+
+static int pasic3_remove(struct platform_device *pdev)
+{
+        struct pasic3_data *asic = platform_get_drvdata(pdev);
+        struct resource *r;
+
+        if (asic->led_pdev)
+                platform_device_unregister(asic->led_pdev);
+        if (asic->ds1wm_pdev)
+                platform_device_unregister(asic->ds1wm_pdev);
+
+        iounmap(asic->mapping);
+        r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+        release_mem_region(r->start, r->end - r->start + 1);
+        kfree(asic);
+        return 0;
+}
+
+static struct platform_driver pasic3_driver = {
+        .driver         = {
+                .name   = "pasic3",
+        },
+        .remove         = pasic3_remove,
+};
+
+static int __init pasic3_base_init(void)
+{
+        return platform_driver_probe(&pasic3_driver, pasic3_probe);
+}
+
+static void __exit pasic3_base_exit(void)
+{
+        platform_driver_unregister(&pasic3_driver);
+}
+
+module_init(pasic3_base_init);
+module_exit(pasic3_base_exit);
+
+MODULE_AUTHOR("Philipp Zabel <philipp.zabel@gmail.com>");
+MODULE_DESCRIPTION("Core driver for HTC PASIC3");
+MODULE_LICENSE("GPL");