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openwrt/target/linux/cns3xxx/patches-3.3/050-cns3xxx_i2c_controller....

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--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -326,6 +326,18 @@ config I2C_BLACKFIN_TWI_CLK_KHZ
help
The unit of the TWI clock is kHz.
+config I2C_CNS3XXX
+ tristate "Cavium CNS3xxx I2C driver"
+ depends on ARCH_CNS3XXX
+ help
+ Support for Cavium CNS3xxx I2C controller driver.
+
+ This driver can also be built as a module. If so, the module
+ will be called i2c-cns3xxx.
+
+ Please note that this driver might be needed to bring up other
+ devices such as Cavium CNS3xxx Ethernet.
+
config I2C_CPM
tristate "Freescale CPM1 or CPM2 (MPC8xx/826x)"
depends on (CPM1 || CPM2) && OF_I2C
--- a/drivers/i2c/busses/Makefile
+++ b/drivers/i2c/busses/Makefile
@@ -83,6 +83,7 @@ obj-$(CONFIG_I2C_ELEKTOR) += i2c-elektor
obj-$(CONFIG_I2C_PCA_ISA) += i2c-pca-isa.o
obj-$(CONFIG_I2C_SIBYTE) += i2c-sibyte.o
obj-$(CONFIG_I2C_STUB) += i2c-stub.o
+obj-$(CONFIG_I2C_CNS3XXX) += i2c-cns3xxx.o
obj-$(CONFIG_SCx200_ACB) += scx200_acb.o
obj-$(CONFIG_SCx200_I2C) += scx200_i2c.o
--- /dev/null
+++ b/drivers/i2c/busses/i2c-cns3xxx.c
@@ -0,0 +1,387 @@
+/*
+ * Cavium CNS3xxx I2C Host Controller
+ *
+ * Copyright 2010 Cavium Network
+ * Copyright 2011 Gateworks Corporation
+ * Chris Lang <clang@gateworks.com>
+ *
+ * This file 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.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <asm/io.h>
+#include <linux/wait.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/slab.h>
+#include <mach/pm.h>
+#include <mach/cns3xxx.h>
+
+/*
+ * We need the memory map
+ */
+
+
+#define MISC_MEM_MAP_VALUE(reg_offset) (*((uint32_t volatile *)(CNS3XXX_MISC_BASE_VIRT + reg_offset)))
+#define MISC_IOCDB_CTRL MISC_MEM_MAP_VALUE(0x020)
+
+#define I2C_MEM_MAP_ADDR(x) (CNS3XXX_SSP_BASE_VIRT + x)
+#define I2C_MEM_MAP_VALUE(x) (*((unsigned int volatile*)I2C_MEM_MAP_ADDR(x)))
+
+#define I2C_CONTROLLER_REG I2C_MEM_MAP_VALUE(0x20)
+#define I2C_TIME_OUT_REG I2C_MEM_MAP_VALUE(0x24)
+#define I2C_SLAVE_ADDRESS_REG I2C_MEM_MAP_VALUE(0x28)
+#define I2C_WRITE_DATA_REG I2C_MEM_MAP_VALUE(0x2C)
+#define I2C_READ_DATA_REG I2C_MEM_MAP_VALUE(0x30)
+#define I2C_INTERRUPT_STATUS_REG I2C_MEM_MAP_VALUE(0x34)
+#define I2C_INTERRUPT_ENABLE_REG I2C_MEM_MAP_VALUE(0x38)
+#define I2C_TWI_OUT_DLY_REG I2C_MEM_MAP_VALUE(0x3C)
+
+#define I2C_BUS_ERROR_FLAG (0x1)
+#define I2C_ACTION_DONE_FLAG (0x2)
+
+#define CNS3xxx_I2C_ENABLE() (I2C_CONTROLLER_REG) |= ((unsigned int)0x1 << 31)
+#define CNS3xxx_I2C_DISABLE() (I2C_CONTROLLER_REG) &= ~((unsigned int)0x1 << 31)
+#define CNS3xxx_I2C_ENABLE_INTR() (I2C_INTERRUPT_ENABLE_REG) |= 0x03
+#define CNS3xxx_I2C_DISABLE_INTR() (I2C_INTERRUPT_ENABLE_REG) &= 0xfc
+
+#define TWI_TIMEOUT (10*HZ)
+#define I2C_100KHZ 100000
+#define I2C_200KHZ 200000
+#define I2C_300KHZ 300000
+#define I2C_400KHZ 400000
+
+#define CNS3xxx_I2C_CLK I2C_100KHZ
+
+#define STATE_DONE 1
+#define STATE_ERROR 2
+
+struct cns3xxx_i2c {
+ void __iomem *base;
+ wait_queue_head_t wait;
+ struct i2c_adapter adap;
+ struct i2c_msg *msg;
+ int state; /* see STATE_ */
+ int rd_wr_len;
+ u8 *buf;
+};
+
+static u32 cns3xxx_i2c_func(struct i2c_adapter *adap)
+{
+ return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+}
+
+static int
+cns3xxx_i2c_xfer_msg(struct i2c_adapter *adap, struct i2c_msg *msg)
+{
+ struct cns3xxx_i2c *i2c = i2c_get_adapdata(adap);
+ int i, j;
+ u8 buf[1] = { 0 };
+
+ if (msg->len == 0) {
+ /*
+ * We are probably doing a probe for a device here,
+ * so set the length to one, and data to 0
+ */
+ msg->len = 1;
+ i2c->buf = buf;
+ } else {
+ i2c->buf = msg->buf;
+ }
+
+ if (msg->flags & I2C_M_TEN) {
+ printk
+ ("%s:%d: Presently the driver does not handle extended addressing\n",
+ __FUNCTION__, __LINE__);
+ return -EINVAL;
+ }
+ i2c->msg = msg;
+
+ for (i = 0; i < msg->len; i++) {
+ if (msg->len - i >= 4)
+ i2c->rd_wr_len = 3;
+ else
+ i2c->rd_wr_len = msg->len - i - 1;
+
+ // Set Data Width and TWI_EN
+ I2C_CONTROLLER_REG = 0x80000000 | (i2c->rd_wr_len << 2) | (i2c->rd_wr_len);
+
+ // Clear Write Reg
+ I2C_WRITE_DATA_REG = 0;
+
+ // Set the slave address
+ I2C_SLAVE_ADDRESS_REG = (msg->addr << 1);
+
+ // Are we Writing
+ if (!(msg->flags & I2C_M_RD)) {
+ I2C_CONTROLLER_REG |= (1 << 4);
+ if (i != 0) {
+ /*
+ * We need to set the address in the first byte.
+ * The base address is going to be in buf[0] and then
+ * it needs to be incremented by i - 1.
+ */
+ i2c->buf--;
+ *i2c->buf = buf[0] + i - 1;
+
+ if (i2c->rd_wr_len < 3) {
+ i += i2c->rd_wr_len;
+ i2c->rd_wr_len++;
+ I2C_CONTROLLER_REG = 0x80000000 | (1 << 4) | (i2c->rd_wr_len << 2) | (i2c->rd_wr_len);
+ } else {
+ i += i2c->rd_wr_len - 1;
+ }
+ } else {
+ i += i2c->rd_wr_len;
+ buf[0] = *i2c->buf;
+ }
+ for (j = 0; j <= i2c->rd_wr_len; j++) {
+ I2C_WRITE_DATA_REG |= ((*i2c->buf++) << (8 * j));
+ }
+ } else {
+ i += i2c->rd_wr_len;
+ }
+
+ // Start the Transfer
+ i2c->state = 0; // Clear out the State
+ I2C_CONTROLLER_REG |= (1 << 6);
+
+ if (wait_event_timeout(i2c->wait, (i2c->state == STATE_ERROR) ||
+ (i2c->state == STATE_DONE), TWI_TIMEOUT)) {
+ if (i2c->state == STATE_ERROR) {
+ return -EIO;
+ }
+ } else {
+ return -ETIMEDOUT;
+ }
+ }
+ return 0;
+}
+
+static int
+cns3xxx_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
+{
+ int i;
+ int ret;
+ for (i = 0; i < num; i++)
+ {
+ ret = cns3xxx_i2c_xfer_msg(adap, &msgs[i]);
+ if (ret < 0) {
+ return ret;
+ }
+ }
+ return num;
+}
+
+
+static struct i2c_algorithm cns3xxx_i2c_algo = {
+ .master_xfer = cns3xxx_i2c_xfer,
+ .functionality = cns3xxx_i2c_func,
+};
+
+static struct i2c_adapter cns3xxx_i2c_adapter = {
+ .owner = THIS_MODULE,
+ .algo = &cns3xxx_i2c_algo,
+ .algo_data = NULL,
+ .nr = 0,
+ .name = "CNS3xxx I2C 0",
+ .retries = 5,
+};
+
+static void cns3xxx_i2c_adapter_init(struct cns3xxx_i2c *i2c)
+{
+ cns3xxx_pwr_clk_en(1 << PM_CLK_GATE_REG_OFFSET_SPI_PCM_I2C);
+ cns3xxx_pwr_power_up(1 << PM_CLK_GATE_REG_OFFSET_SPI_PCM_I2C);
+ cns3xxx_pwr_soft_rst(1 << PM_CLK_GATE_REG_OFFSET_SPI_PCM_I2C);
+
+ /* Disable the I2C */
+ I2C_CONTROLLER_REG = 0; /* Disabled the I2C */
+
+ //enable SCL and SDA which share pin with GPIOB_PIN_EN(0x18)
+ //GPIOB[12]: SCL
+ //GPIOB[13]: SDA
+ (*(u32*)(CNS3XXX_MISC_BASE_VIRT+0x18)) |= ((1<<12)|(1<<13));
+
+ MISC_IOCDB_CTRL &= ~0x300;
+ MISC_IOCDB_CTRL |= 0x300; //21mA...
+
+ /* Check the Reg Dump when testing */
+ I2C_TIME_OUT_REG =
+ ((((((cns3xxx_cpu_clock()*(1000000/8)) / (2 * CNS3xxx_I2C_CLK)) -
+ 1) & 0x3FF) << 8) | (1 << 7) | 0x7F);
+ I2C_TWI_OUT_DLY_REG |= 0x3;
+
+ /* Enable The Interrupt */
+ CNS3xxx_I2C_ENABLE_INTR();
+
+ /* Clear Interrupt Status (0x2 | 0x1) */
+ I2C_INTERRUPT_STATUS_REG |= (I2C_ACTION_DONE_FLAG | I2C_BUS_ERROR_FLAG);
+
+ /* Enable the I2C Controller */
+ CNS3xxx_I2C_ENABLE();
+}
+
+static irqreturn_t cns3xxx_i2c_isr(int irq, void *dev_id)
+{
+ struct cns3xxx_i2c *i2c = dev_id;
+ int i;
+ uint32_t stat = I2C_INTERRUPT_STATUS_REG;
+
+ /* Clear Interrupt */
+ I2C_INTERRUPT_STATUS_REG |= 0x1;
+
+ if (stat & I2C_BUS_ERROR_FLAG) {
+ i2c->state = STATE_ERROR;
+ } else {
+ if (i2c->msg->flags & I2C_M_RD) {
+ for (i = 0; i <= i2c->rd_wr_len; i++)
+ {
+ *i2c->buf++ = ((I2C_READ_DATA_REG >> (8 * i)) & 0xff);
+ }
+ }
+ i2c->state = STATE_DONE;
+ }
+ wake_up(&i2c->wait);
+ return IRQ_HANDLED;
+}
+
+static int __devinit cns3xxx_i2c_probe(struct platform_device *pdev)
+{
+ struct cns3xxx_i2c *i2c;
+ struct resource *res, *res2;
+ int ret;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res) {
+ printk("%s: IORESOURCE_MEM not defined \n", __FUNCTION__);
+ return -ENODEV;
+ }
+
+ res2 = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+ if (!res2) {
+ printk("%s: IORESOURCE_IRQ not defined \n", __FUNCTION__);
+ return -ENODEV;
+ }
+
+ i2c = kzalloc(sizeof(*i2c), GFP_KERNEL);
+ if (!i2c)
+ return -ENOMEM;
+
+ if (!request_mem_region(res->start, res->end - res->start + 1,
+ pdev->name)) {
+ dev_err(&pdev->dev, "Memory region busy\n");
+ ret = -EBUSY;
+ goto request_mem_failed;
+ }
+
+ i2c->base = ioremap(res->start, res->end - res->start + 1);
+ if (!i2c->base) {
+ dev_err(&pdev->dev, "Unable to map registers\n");
+ ret = -EIO;
+ goto map_failed;
+ }
+
+ cns3xxx_i2c_adapter_init(i2c);
+
+ init_waitqueue_head(&i2c->wait);
+ ret = request_irq(res2->start, cns3xxx_i2c_isr, 0, pdev->name, i2c);
+ if (ret) {
+ dev_err(&pdev->dev, "Cannot claim IRQ\n");
+ goto request_irq_failed;
+ }
+
+ platform_set_drvdata(pdev, i2c);
+ i2c->adap = cns3xxx_i2c_adapter;
+ i2c_set_adapdata(&i2c->adap, i2c);
+ i2c->adap.dev.parent = &pdev->dev;
+
+ /* add i2c adapter to i2c tree */
+ ret = i2c_add_numbered_adapter(&i2c->adap);
+ if (ret) {
+ dev_err(&pdev->dev, "Failed to add adapter\n");
+ goto add_adapter_failed;
+ }
+
+ return 0;
+
+ add_adapter_failed:
+ free_irq(res2->start, i2c);
+ request_irq_failed:
+ iounmap(i2c->base);
+ map_failed:
+ release_mem_region(res->start, res->end - res->start + 1);
+ request_mem_failed:
+ kfree(i2c);
+
+ return ret;
+}
+
+static int __devexit cns3xxx_i2c_remove(struct platform_device *pdev)
+{
+ struct cns3xxx_i2c *i2c = platform_get_drvdata(pdev);
+ struct resource *res;
+
+ /* disable i2c logic */
+ CNS3xxx_I2C_DISABLE_INTR();
+ CNS3xxx_I2C_DISABLE();
+ /* remove adapter & data */
+ i2c_del_adapter(&i2c->adap);
+ platform_set_drvdata(pdev, NULL);
+
+ res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+ if (res)
+ free_irq(res->start, i2c);
+
+ iounmap(i2c->base);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (res)
+ release_mem_region(res->start, res->end - res->start + 1);
+
+ kfree(i2c);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM
+#warning "CONFIG_PM defined: suspend and resume not implemented"
+#define cns3xxx_i2c_suspend NULL
+#define cns3xxx_i2c_resume NULL
+#else
+#define cns3xxx_i2c_suspend NULL
+#define cns3xxx_i2c_resume NULL
+#endif
+
+static struct platform_driver cns3xxx_i2c_driver = {
+ .probe = cns3xxx_i2c_probe,
+ .remove = cns3xxx_i2c_remove,
+ .suspend = cns3xxx_i2c_suspend,
+ .resume = cns3xxx_i2c_resume,
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = "cns3xxx-i2c",
+ },
+};
+
+static int __init cns3xxx_i2c_init(void)
+{
+ return platform_driver_register(&cns3xxx_i2c_driver);
+}
+
+static void __exit cns3xxx_i2c_exit(void)
+{
+ platform_driver_unregister(&cns3xxx_i2c_driver);
+}
+
+module_init(cns3xxx_i2c_init);
+module_exit(cns3xxx_i2c_exit);
+
+MODULE_AUTHOR("Cavium Networks");
+MODULE_DESCRIPTION("Cavium CNS3XXX I2C Controller");
+MODULE_LICENSE("GPL");
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