+++ /dev/null
-From 225f36695bb07dad9510f9affd79e63f1a44a195 Mon Sep 17 00:00:00 2001
-From: John Crispin <blogic@openwrt.org>
-Date: Sun, 27 Jul 2014 09:52:56 +0100
-Subject: [PATCH 52/57] i2c: MIPS: adds ralink I2C driver
-
-Signed-off-by: John Crispin <blogic@openwrt.org>
----
- .../devicetree/bindings/i2c/i2c-ralink.txt | 27 ++
- drivers/i2c/busses/Kconfig | 4 +
- drivers/i2c/busses/Makefile | 1 +
- drivers/i2c/busses/i2c-ralink.c | 274 ++++++++++++++++++++
- 4 files changed, 306 insertions(+)
- create mode 100644 Documentation/devicetree/bindings/i2c/i2c-ralink.txt
- create mode 100644 drivers/i2c/busses/i2c-ralink.c
-
---- /dev/null
-+++ b/Documentation/devicetree/bindings/i2c/i2c-ralink.txt
-@@ -0,0 +1,27 @@
-+I2C for Ralink platforms
-+
-+Required properties :
-+- compatible : Must be "link,rt3052-i2c"
-+- reg: physical base address of the controller and length of memory mapped
-+ region.
-+- #address-cells = <1>;
-+- #size-cells = <0>;
-+
-+Optional properties:
-+- Child nodes conforming to i2c bus binding
-+
-+Example :
-+
-+palmbus@10000000 {
-+ i2c@900 {
-+ compatible = "link,rt3052-i2c";
-+ reg = <0x900 0x100>;
-+ #address-cells = <1>;
-+ #size-cells = <0>;
-+
-+ hwmon@4b {
-+ compatible = "national,lm92";
-+ reg = <0x4b>;
-+ };
-+ };
-+};
---- a/drivers/i2c/busses/Kconfig
-+++ b/drivers/i2c/busses/Kconfig
-@@ -711,6 +711,10 @@ config I2C_RK3X
- This driver can also be built as a module. If so, the module will
- be called i2c-rk3x.
-
-+config I2C_RALINK
-+ tristate "Ralink I2C Controller"
-+ select OF_I2C
-+
- config HAVE_S3C2410_I2C
- bool
- help
---- a/drivers/i2c/busses/Makefile
-+++ b/drivers/i2c/busses/Makefile
-@@ -66,6 +66,7 @@ obj-$(CONFIG_I2C_PNX) += i2c-pnx.o
- obj-$(CONFIG_I2C_PUV3) += i2c-puv3.o
- obj-$(CONFIG_I2C_PXA) += i2c-pxa.o
- obj-$(CONFIG_I2C_PXA_PCI) += i2c-pxa-pci.o
-+obj-$(CONFIG_I2C_RALINK) += i2c-ralink.o
- obj-$(CONFIG_I2C_QUP) += i2c-qup.o
- obj-$(CONFIG_I2C_RIIC) += i2c-riic.o
- obj-$(CONFIG_I2C_RK3X) += i2c-rk3x.o
---- /dev/null
-+++ b/drivers/i2c/busses/i2c-ralink.c
-@@ -0,0 +1,327 @@
-+/*
-+ * drivers/i2c/busses/i2c-ralink.c
-+ *
-+ * Copyright (C) 2013 Steven Liu <steven_liu@mediatek.com>
-+ *
-+ * Improve driver for i2cdetect from i2c-tools to detect i2c devices on the bus.
-+ * (C) 2014 Sittisak <sittisaks@hotmail.com>
-+ *
-+ * This software is licensed under the terms of the GNU General Public
-+ * License version 2, as published by the Free Software Foundation, and
-+ * may be copied, distributed, and modified under those terms.
-+ *
-+ * This program is distributed in the hope that it will be useful,
-+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
-+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-+ * GNU General Public License for more details.
-+ *
-+ */
-+
-+#include <linux/interrupt.h>
-+#include <linux/kernel.h>
-+#include <linux/module.h>
-+#include <linux/reset.h>
-+#include <linux/delay.h>
-+#include <linux/slab.h>
-+#include <linux/init.h>
-+#include <linux/errno.h>
-+#include <linux/platform_device.h>
-+#include <linux/of_platform.h>
-+#include <linux/i2c.h>
-+#include <linux/io.h>
-+#include <linux/err.h>
-+
-+#include <asm/mach-ralink/ralink_regs.h>
-+
-+#define REG_CONFIG_REG 0x00
-+#define REG_CLKDIV_REG 0x04
-+#define REG_DEVADDR_REG 0x08
-+#define REG_ADDR_REG 0x0C
-+#define REG_DATAOUT_REG 0x10
-+#define REG_DATAIN_REG 0x14
-+#define REG_STATUS_REG 0x18
-+#define REG_STARTXFR_REG 0x1C
-+#define REG_BYTECNT_REG 0x20
-+#define REG_SM0CFG2 0x28
-+#define REG_SM0CTL0 0x40
-+
-+#define I2C_STARTERR BIT(4)
-+#define I2C_ACKERR BIT(3)
-+#define I2C_DATARDY BIT(2)
-+#define I2C_SDOEMPTY BIT(1)
-+#define I2C_BUSY BIT(0)
-+
-+#define I2C_DEVADLEN_7 (6 << 2)
-+#define I2C_ADDRDIS BIT(1)
-+
-+#define CLKDIV_VALUE 200 // clock rate is 40M, 40M / (200*2) = 100k (standard i2c bus rate).
-+//#define CLKDIV_VALUE 50 // clock rate is 40M, 40M / (50*2) = 400k (fast i2c bus rate).
-+
-+#define READ_CMD 0x01
-+#define WRITE_CMD 0x00
-+#define READ_BLOCK 64
-+
-+#define SM0CTL0_OD BIT(31)
-+#define SM0CTL0_VTRIG BIT(28)
-+#define SM0CTL0_OUTHI BIT(6)
-+#define SM0CTL0_STRETCH BIT(1)
-+#define SM0CTL0_DEFAULT (SM0CTL0_OD | SM0CTL0_VTRIG | SM0CTL0_OUTHI | SM0CTL0_STRETCH)
-+
-+/* timeout waiting for I2C devices to respond (clock streching) */
-+#define RT_I2C_TIMEOUT (msecs_to_jiffies(1000))
-+
-+enum {
-+ I2C_TYPE_RALINK,
-+ I2C_TYPE_MEDIATEK,
-+};
-+
-+static void __iomem *membase;
-+static struct i2c_adapter *adapter;
-+static int hw_type;
-+
-+static void rt_i2c_w32(u32 val, unsigned reg)
-+{
-+ iowrite32(val, membase + reg);
-+}
-+
-+static u32 rt_i2c_r32(unsigned reg)
-+{
-+ return ioread32(membase + reg);
-+}
-+
-+static inline int rt_i2c_get_ack(void)
-+{
-+ return (rt_i2c_r32(REG_STATUS_REG) & I2C_ACKERR) ? -EIO : 0;
-+}
-+
-+static inline int rt_i2c_wait_rx_done(void)
-+{
-+ unsigned long timeout;
-+
-+ timeout = jiffies + RT_I2C_TIMEOUT;
-+
-+ do {
-+ if (time_after(jiffies, timeout))
-+ return (-ETIMEDOUT);
-+
-+ } while (!(rt_i2c_r32(REG_STATUS_REG) & I2C_DATARDY));
-+
-+ return 0;
-+}
-+
-+static inline int rt_i2c_wait_idle(void)
-+{
-+ unsigned long timeout;
-+
-+ timeout = jiffies + RT_I2C_TIMEOUT;
-+
-+ do {
-+ if (time_after(jiffies, timeout)) {
-+ printk("i2c-read line busy\n");
-+ return 1;
-+ }
-+ } while (rt_i2c_r32(REG_STATUS_REG) & I2C_BUSY);
-+
-+ return 0;
-+}
-+
-+static inline int rt_i2c_wait_tx_done(void)
-+{
-+ unsigned long timeout;
-+
-+ timeout = jiffies + RT_I2C_TIMEOUT;
-+
-+ do {
-+ if (time_after(jiffies, timeout))
-+ return (-ETIMEDOUT);
-+
-+ } while (!(rt_i2c_r32(REG_STATUS_REG) & I2C_SDOEMPTY));
-+
-+ return 0;
-+}
-+
-+static int rt_i2c_handle_msg(struct i2c_adapter *a, struct i2c_msg* msg)
-+{
-+ int i = 0, j = 0, pos = 0;
-+ int nblock = msg->len / READ_BLOCK;
-+ int rem = msg->len % READ_BLOCK;
-+ int ret = 0;
-+
-+ if (msg->flags & I2C_M_TEN) {
-+ printk("10 bits addr not supported\n");
-+ return -EINVAL;
-+ }
-+
-+ if (msg->flags & I2C_M_RD) {
-+ for (i = 0; i < nblock; i++) {
-+ if (rt_i2c_wait_idle())
-+ return -ETIMEDOUT;
-+ rt_i2c_w32(READ_BLOCK - 1, REG_BYTECNT_REG);
-+ rt_i2c_w32(READ_CMD, REG_STARTXFR_REG);
-+ for (j = 0; j < READ_BLOCK; j++) {
-+ if (rt_i2c_wait_rx_done() < 0)
-+ ret = rt_i2c_wait_rx_done();
-+ if (rt_i2c_get_ack() < 0)
-+ ret = rt_i2c_get_ack();
-+ msg->buf[pos++] = rt_i2c_r32(REG_DATAIN_REG);
-+ }
-+ }
-+
-+ if (rt_i2c_wait_idle())
-+ return -ETIMEDOUT;
-+ if (rem) {
-+ rt_i2c_w32(rem - 1, REG_BYTECNT_REG);
-+ rt_i2c_w32(READ_CMD, REG_STARTXFR_REG);
-+ }
-+ for (i = 0; i < rem; i++) {
-+ if (rt_i2c_wait_rx_done() < 0)
-+ ret = rt_i2c_wait_rx_done();
-+ if (rt_i2c_get_ack() < 0)
-+ ret = rt_i2c_get_ack();
-+
-+ msg->buf[pos++] = rt_i2c_r32(REG_DATAIN_REG);
-+ }
-+ } else {
-+ if (rt_i2c_wait_idle())
-+ return -ETIMEDOUT;
-+ rt_i2c_w32(msg->len - 1, REG_BYTECNT_REG);
-+ for (i = 0; i < msg->len; i++) {
-+ rt_i2c_w32(msg->buf[i], REG_DATAOUT_REG);
-+ rt_i2c_w32(WRITE_CMD, REG_STARTXFR_REG);
-+
-+ if (rt_i2c_wait_tx_done() < 0)
-+ ret = rt_i2c_wait_tx_done();
-+ if (rt_i2c_get_ack() < 0)
-+ ret = rt_i2c_get_ack();
-+ }
-+ }
-+
-+ return ret;
-+}
-+
-+static int rt_i2c_master_xfer(struct i2c_adapter *a, struct i2c_msg *m, int n)
-+{
-+ int i = 0;
-+ int ret = 0;
-+
-+ if (rt_i2c_wait_idle())
-+ return -ETIMEDOUT;
-+
-+ device_reset(a->dev.parent);
-+
-+ rt_i2c_w32(m->addr, REG_DEVADDR_REG);
-+ rt_i2c_w32(I2C_DEVADLEN_7 | I2C_ADDRDIS, REG_CONFIG_REG);
-+ if (hw_type == I2C_TYPE_RALINK) {
-+ rt_i2c_w32(CLKDIV_VALUE, REG_CLKDIV_REG);
-+ } else {
-+ rt_i2c_w32((CLKDIV_VALUE << 16) | SM0CTL0_DEFAULT, REG_SM0CTL0);
-+ rt_i2c_w32(1, REG_SM0CFG2);
-+ }
-+
-+ for (i = 0; i < n && !ret; i++) {
-+ ret = rt_i2c_handle_msg(a, &m[i]);
-+
-+ if (ret < 0) {
-+ return ret;
-+ }
-+ }
-+
-+ return n;
-+}
-+
-+static u32 rt_i2c_func(struct i2c_adapter *a)
-+{
-+ return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
-+}
-+
-+static const struct i2c_algorithm rt_i2c_algo = {
-+ .master_xfer = rt_i2c_master_xfer,
-+ .functionality = rt_i2c_func,
-+};
-+
-+static const struct of_device_id i2c_rt_dt_ids[] = {
-+ { .compatible = "ralink,rt2880-i2c", .data = (void *) I2C_TYPE_RALINK },
-+ { .compatible = "mediatek,mt7628-i2c", .data = (void *) I2C_TYPE_MEDIATEK },
-+ { /* sentinel */ }
-+};
-+
-+MODULE_DEVICE_TABLE(of, i2c_rt_dt_ids);
-+
-+static int rt_i2c_probe(struct platform_device *pdev)
-+{
-+ struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-+ const struct of_device_id *match;
-+ int ret;
-+
-+ match = of_match_device(i2c_rt_dt_ids, &pdev->dev);
-+ hw_type = (int) match->data;
-+
-+ if (!res) {
-+ dev_err(&pdev->dev, "no memory resource found\n");
-+ return -ENODEV;
-+ }
-+
-+ adapter = devm_kzalloc(&pdev->dev, sizeof(struct i2c_adapter), GFP_KERNEL);
-+ if (!adapter) {
-+ dev_err(&pdev->dev, "failed to allocate i2c_adapter\n");
-+ return -ENOMEM;
-+ }
-+
-+ membase = devm_ioremap_resource(&pdev->dev, res);
-+ if (IS_ERR(membase))
-+ return PTR_ERR(membase);
-+
-+ strlcpy(adapter->name, dev_name(&pdev->dev), sizeof(adapter->name));
-+ adapter->owner = THIS_MODULE;
-+ adapter->nr = pdev->id;
-+ adapter->timeout = HZ;
-+ adapter->algo = &rt_i2c_algo;
-+ adapter->class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
-+ adapter->dev.parent = &pdev->dev;
-+ adapter->dev.of_node = pdev->dev.of_node;
-+
-+ ret = i2c_add_numbered_adapter(adapter);
-+ if (ret)
-+ return ret;
-+
-+ platform_set_drvdata(pdev, adapter);
-+
-+ dev_info(&pdev->dev, "loaded\n");
-+
-+ return 0;
-+}
-+
-+static int rt_i2c_remove(struct platform_device *pdev)
-+{
-+ platform_set_drvdata(pdev, NULL);
-+
-+ return 0;
-+}
-+
-+static struct platform_driver rt_i2c_driver = {
-+ .probe = rt_i2c_probe,
-+ .remove = rt_i2c_remove,
-+ .driver = {
-+ .owner = THIS_MODULE,
-+ .name = "i2c-ralink",
-+ .of_match_table = i2c_rt_dt_ids,
-+ },
-+};
-+
-+static int __init i2c_rt_init (void)
-+{
-+ return platform_driver_register(&rt_i2c_driver);
-+}
-+subsys_initcall(i2c_rt_init);
-+
-+static void __exit i2c_rt_exit (void)
-+{
-+ platform_driver_unregister(&rt_i2c_driver);
-+}
-+
-+module_exit (i2c_rt_exit);
-+
-+MODULE_AUTHOR("Steven Liu <steven_liu@mediatek.com>");
-+MODULE_DESCRIPTION("Ralink I2c host driver");
-+MODULE_LICENSE("GPL");
-+MODULE_ALIAS("platform:Ralink-I2C");
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