From db811ca0f48578f9940f49f284ac81e336b264ad Mon Sep 17 00:00:00 2001 From: Colin Cross Date: Sun, 20 Feb 2011 17:14:21 -0800 Subject: i2c: tegra: Add i2c support Adds I2C bus driver for nVidia Tegra SoCs. Tegra includes 4 I2C controllers, one of which is inside the Dynamic Voltage Controller and has a slightly different register map. Signed-off-by: Colin Cross Signed-off-by: Ben Dooks --- drivers/i2c/busses/Kconfig | 7 + drivers/i2c/busses/Makefile | 1 + drivers/i2c/busses/i2c-tegra.c | 700 +++++++++++++++++++++++++++++++++++++++++ 3 files changed, 708 insertions(+) create mode 100644 drivers/i2c/busses/i2c-tegra.c (limited to 'drivers/i2c/busses') diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig index 113505a6434e..a5f48dc3b81f 100644 --- a/drivers/i2c/busses/Kconfig +++ b/drivers/i2c/busses/Kconfig @@ -607,6 +607,13 @@ config I2C_STU300 This driver can also be built as a module. If so, the module will be called i2c-stu300. +config I2C_TEGRA + tristate "NVIDIA Tegra internal I2C controller" + depends on ARCH_TEGRA + help + If you say yes to this option, support will be included for the + I2C controller embedded in NVIDIA Tegra SOCs + config I2C_VERSATILE tristate "ARM Versatile/Realview I2C bus support" depends on ARCH_VERSATILE || ARCH_REALVIEW || ARCH_VEXPRESS diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile index 9d2d0ec7fb23..a0d4afe05ea2 100644 --- a/drivers/i2c/busses/Makefile +++ b/drivers/i2c/busses/Makefile @@ -58,6 +58,7 @@ obj-$(CONFIG_I2C_SH7760) += i2c-sh7760.o obj-$(CONFIG_I2C_SH_MOBILE) += i2c-sh_mobile.o obj-$(CONFIG_I2C_SIMTEC) += i2c-simtec.o obj-$(CONFIG_I2C_STU300) += i2c-stu300.o +obj-$(CONFIG_I2C_TEGRA) += i2c-tegra.o obj-$(CONFIG_I2C_VERSATILE) += i2c-versatile.o obj-$(CONFIG_I2C_OCTEON) += i2c-octeon.o obj-$(CONFIG_I2C_XILINX) += i2c-xiic.o diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c new file mode 100644 index 000000000000..3921f664c9c3 --- /dev/null +++ b/drivers/i2c/busses/i2c-tegra.c @@ -0,0 +1,700 @@ +/* + * drivers/i2c/busses/i2c-tegra.c + * + * Copyright (C) 2010 Google, Inc. + * Author: Colin Cross + * + * 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 +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +#include + +#define TEGRA_I2C_TIMEOUT (msecs_to_jiffies(1000)) +#define BYTES_PER_FIFO_WORD 4 + +#define I2C_CNFG 0x000 +#define I2C_CNFG_PACKET_MODE_EN (1<<10) +#define I2C_CNFG_NEW_MASTER_FSM (1<<11) +#define I2C_SL_CNFG 0x020 +#define I2C_SL_CNFG_NEWSL (1<<2) +#define I2C_SL_ADDR1 0x02c +#define I2C_TX_FIFO 0x050 +#define I2C_RX_FIFO 0x054 +#define I2C_PACKET_TRANSFER_STATUS 0x058 +#define I2C_FIFO_CONTROL 0x05c +#define I2C_FIFO_CONTROL_TX_FLUSH (1<<1) +#define I2C_FIFO_CONTROL_RX_FLUSH (1<<0) +#define I2C_FIFO_CONTROL_TX_TRIG_SHIFT 5 +#define I2C_FIFO_CONTROL_RX_TRIG_SHIFT 2 +#define I2C_FIFO_STATUS 0x060 +#define I2C_FIFO_STATUS_TX_MASK 0xF0 +#define I2C_FIFO_STATUS_TX_SHIFT 4 +#define I2C_FIFO_STATUS_RX_MASK 0x0F +#define I2C_FIFO_STATUS_RX_SHIFT 0 +#define I2C_INT_MASK 0x064 +#define I2C_INT_STATUS 0x068 +#define I2C_INT_PACKET_XFER_COMPLETE (1<<7) +#define I2C_INT_ALL_PACKETS_XFER_COMPLETE (1<<6) +#define I2C_INT_TX_FIFO_OVERFLOW (1<<5) +#define I2C_INT_RX_FIFO_UNDERFLOW (1<<4) +#define I2C_INT_NO_ACK (1<<3) +#define I2C_INT_ARBITRATION_LOST (1<<2) +#define I2C_INT_TX_FIFO_DATA_REQ (1<<1) +#define I2C_INT_RX_FIFO_DATA_REQ (1<<0) +#define I2C_CLK_DIVISOR 0x06c + +#define DVC_CTRL_REG1 0x000 +#define DVC_CTRL_REG1_INTR_EN (1<<10) +#define DVC_CTRL_REG2 0x004 +#define DVC_CTRL_REG3 0x008 +#define DVC_CTRL_REG3_SW_PROG (1<<26) +#define DVC_CTRL_REG3_I2C_DONE_INTR_EN (1<<30) +#define DVC_STATUS 0x00c +#define DVC_STATUS_I2C_DONE_INTR (1<<30) + +#define I2C_ERR_NONE 0x00 +#define I2C_ERR_NO_ACK 0x01 +#define I2C_ERR_ARBITRATION_LOST 0x02 + +#define PACKET_HEADER0_HEADER_SIZE_SHIFT 28 +#define PACKET_HEADER0_PACKET_ID_SHIFT 16 +#define PACKET_HEADER0_CONT_ID_SHIFT 12 +#define PACKET_HEADER0_PROTOCOL_I2C (1<<4) + +#define I2C_HEADER_HIGHSPEED_MODE (1<<22) +#define I2C_HEADER_CONT_ON_NAK (1<<21) +#define I2C_HEADER_SEND_START_BYTE (1<<20) +#define I2C_HEADER_READ (1<<19) +#define I2C_HEADER_10BIT_ADDR (1<<18) +#define I2C_HEADER_IE_ENABLE (1<<17) +#define I2C_HEADER_REPEAT_START (1<<16) +#define I2C_HEADER_MASTER_ADDR_SHIFT 12 +#define I2C_HEADER_SLAVE_ADDR_SHIFT 1 + +/** + * struct tegra_i2c_dev - per device i2c context + * @dev: device reference for power management + * @adapter: core i2c layer adapter information + * @clk: clock reference for i2c controller + * @i2c_clk: clock reference for i2c bus + * @iomem: memory resource for registers + * @base: ioremapped registers cookie + * @cont_id: i2c controller id, used for for packet header + * @irq: irq number of transfer complete interrupt + * @is_dvc: identifies the DVC i2c controller, has a different register layout + * @msg_complete: transfer completion notifier + * @msg_err: error code for completed message + * @msg_buf: pointer to current message data + * @msg_buf_remaining: size of unsent data in the message buffer + * @msg_read: identifies read transfers + * @bus_clk_rate: current i2c bus clock rate + * @is_suspended: prevents i2c controller accesses after suspend is called + */ +struct tegra_i2c_dev { + struct device *dev; + struct i2c_adapter adapter; + struct clk *clk; + struct clk *i2c_clk; + struct resource *iomem; + void __iomem *base; + int cont_id; + int irq; + int is_dvc; + struct completion msg_complete; + int msg_err; + u8 *msg_buf; + size_t msg_buf_remaining; + int msg_read; + unsigned long bus_clk_rate; + bool is_suspended; +}; + +static void dvc_writel(struct tegra_i2c_dev *i2c_dev, u32 val, unsigned long reg) +{ + writel(val, i2c_dev->base + reg); +} + +static u32 dvc_readl(struct tegra_i2c_dev *i2c_dev, unsigned long reg) +{ + return readl(i2c_dev->base + reg); +} + +/* + * i2c_writel and i2c_readl will offset the register if necessary to talk + * to the I2C block inside the DVC block + */ +static unsigned long tegra_i2c_reg_addr(struct tegra_i2c_dev *i2c_dev, + unsigned long reg) +{ + if (i2c_dev->is_dvc) + reg += (reg >= I2C_TX_FIFO) ? 0x10 : 0x40; + return reg; +} + +static void i2c_writel(struct tegra_i2c_dev *i2c_dev, u32 val, + unsigned long reg) +{ + writel(val, i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg)); +} + +static u32 i2c_readl(struct tegra_i2c_dev *i2c_dev, unsigned long reg) +{ + return readl(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg)); +} + +static void i2c_writesl(struct tegra_i2c_dev *i2c_dev, void *data, + unsigned long reg, int len) +{ + writesl(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg), data, len); +} + +static void i2c_readsl(struct tegra_i2c_dev *i2c_dev, void *data, + unsigned long reg, int len) +{ + readsl(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg), data, len); +} + +static void tegra_i2c_mask_irq(struct tegra_i2c_dev *i2c_dev, u32 mask) +{ + u32 int_mask = i2c_readl(i2c_dev, I2C_INT_MASK); + int_mask &= ~mask; + i2c_writel(i2c_dev, int_mask, I2C_INT_MASK); +} + +static void tegra_i2c_unmask_irq(struct tegra_i2c_dev *i2c_dev, u32 mask) +{ + u32 int_mask = i2c_readl(i2c_dev, I2C_INT_MASK); + int_mask |= mask; + i2c_writel(i2c_dev, int_mask, I2C_INT_MASK); +} + +static int tegra_i2c_flush_fifos(struct tegra_i2c_dev *i2c_dev) +{ + unsigned long timeout = jiffies + HZ; + u32 val = i2c_readl(i2c_dev, I2C_FIFO_CONTROL); + val |= I2C_FIFO_CONTROL_TX_FLUSH | I2C_FIFO_CONTROL_RX_FLUSH; + i2c_writel(i2c_dev, val, I2C_FIFO_CONTROL); + + while (i2c_readl(i2c_dev, I2C_FIFO_CONTROL) & + (I2C_FIFO_CONTROL_TX_FLUSH | I2C_FIFO_CONTROL_RX_FLUSH)) { + if (time_after(jiffies, timeout)) { + dev_warn(i2c_dev->dev, "timeout waiting for fifo flush\n"); + return -ETIMEDOUT; + } + msleep(1); + } + return 0; +} + +static int tegra_i2c_empty_rx_fifo(struct tegra_i2c_dev *i2c_dev) +{ + u32 val; + int rx_fifo_avail; + u8 *buf = i2c_dev->msg_buf; + size_t buf_remaining = i2c_dev->msg_buf_remaining; + int words_to_transfer; + + val = i2c_readl(i2c_dev, I2C_FIFO_STATUS); + rx_fifo_avail = (val & I2C_FIFO_STATUS_RX_MASK) >> + I2C_FIFO_STATUS_RX_SHIFT; + + /* Rounds down to not include partial word at the end of buf */ + words_to_transfer = buf_remaining / BYTES_PER_FIFO_WORD; + if (words_to_transfer > rx_fifo_avail) + words_to_transfer = rx_fifo_avail; + + i2c_readsl(i2c_dev, buf, I2C_RX_FIFO, words_to_transfer); + + buf += words_to_transfer * BYTES_PER_FIFO_WORD; + buf_remaining -= words_to_transfer * BYTES_PER_FIFO_WORD; + rx_fifo_avail -= words_to_transfer; + + /* + * If there is a partial word at the end of buf, handle it manually to + * prevent overwriting past the end of buf + */ + if (rx_fifo_avail > 0 && buf_remaining > 0) { + BUG_ON(buf_remaining > 3); + val = i2c_readl(i2c_dev, I2C_RX_FIFO); + memcpy(buf, &val, buf_remaining); + buf_remaining = 0; + rx_fifo_avail--; + } + + BUG_ON(rx_fifo_avail > 0 && buf_remaining > 0); + i2c_dev->msg_buf_remaining = buf_remaining; + i2c_dev->msg_buf = buf; + return 0; +} + +static int tegra_i2c_fill_tx_fifo(struct tegra_i2c_dev *i2c_dev) +{ + u32 val; + int tx_fifo_avail; + u8 *buf = i2c_dev->msg_buf; + size_t buf_remaining = i2c_dev->msg_buf_remaining; + int words_to_transfer; + + val = i2c_readl(i2c_dev, I2C_FIFO_STATUS); + tx_fifo_avail = (val & I2C_FIFO_STATUS_TX_MASK) >> + I2C_FIFO_STATUS_TX_SHIFT; + + /* Rounds down to not include partial word at the end of buf */ + words_to_transfer = buf_remaining / BYTES_PER_FIFO_WORD; + if (words_to_transfer > tx_fifo_avail) + words_to_transfer = tx_fifo_avail; + + i2c_writesl(i2c_dev, buf, I2C_TX_FIFO, words_to_transfer); + + buf += words_to_transfer * BYTES_PER_FIFO_WORD; + buf_remaining -= words_to_transfer * BYTES_PER_FIFO_WORD; + tx_fifo_avail -= words_to_transfer; + + /* + * If there is a partial word at the end of buf, handle it manually to + * prevent reading past the end of buf, which could cross a page + * boundary and fault. + */ + if (tx_fifo_avail > 0 && buf_remaining > 0) { + BUG_ON(buf_remaining > 3); + memcpy(&val, buf, buf_remaining); + i2c_writel(i2c_dev, val, I2C_TX_FIFO); + buf_remaining = 0; + tx_fifo_avail--; + } + + BUG_ON(tx_fifo_avail > 0 && buf_remaining > 0); + i2c_dev->msg_buf_remaining = buf_remaining; + i2c_dev->msg_buf = buf; + return 0; +} + +/* + * One of the Tegra I2C blocks is inside the DVC (Digital Voltage Controller) + * block. This block is identical to the rest of the I2C blocks, except that + * it only supports master mode, it has registers moved around, and it needs + * some extra init to get it into I2C mode. The register moves are handled + * by i2c_readl and i2c_writel + */ +static void tegra_dvc_init(struct tegra_i2c_dev *i2c_dev) +{ + u32 val = 0; + val = dvc_readl(i2c_dev, DVC_CTRL_REG3); + val |= DVC_CTRL_REG3_SW_PROG; + val |= DVC_CTRL_REG3_I2C_DONE_INTR_EN; + dvc_writel(i2c_dev, val, DVC_CTRL_REG3); + + val = dvc_readl(i2c_dev, DVC_CTRL_REG1); + val |= DVC_CTRL_REG1_INTR_EN; + dvc_writel(i2c_dev, val, DVC_CTRL_REG1); +} + +static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev) +{ + u32 val; + int err = 0; + + clk_enable(i2c_dev->clk); + + tegra_periph_reset_assert(i2c_dev->clk); + udelay(2); + tegra_periph_reset_deassert(i2c_dev->clk); + + if (i2c_dev->is_dvc) + tegra_dvc_init(i2c_dev); + + val = I2C_CNFG_NEW_MASTER_FSM | I2C_CNFG_PACKET_MODE_EN; + i2c_writel(i2c_dev, val, I2C_CNFG); + i2c_writel(i2c_dev, 0, I2C_INT_MASK); + clk_set_rate(i2c_dev->clk, i2c_dev->bus_clk_rate * 8); + + val = 7 << I2C_FIFO_CONTROL_TX_TRIG_SHIFT | + 0 << I2C_FIFO_CONTROL_RX_TRIG_SHIFT; + i2c_writel(i2c_dev, val, I2C_FIFO_CONTROL); + + if (tegra_i2c_flush_fifos(i2c_dev)) + err = -ETIMEDOUT; + + clk_disable(i2c_dev->clk); + return err; +} + +static irqreturn_t tegra_i2c_isr(int irq, void *dev_id) +{ + u32 status; + const u32 status_err = I2C_INT_NO_ACK | I2C_INT_ARBITRATION_LOST; + struct tegra_i2c_dev *i2c_dev = dev_id; + + status = i2c_readl(i2c_dev, I2C_INT_STATUS); + + if (status == 0) { + dev_warn(i2c_dev->dev, "interrupt with no status\n"); + return IRQ_NONE; + } + + if (unlikely(status & status_err)) { + if (status & I2C_INT_NO_ACK) + i2c_dev->msg_err |= I2C_ERR_NO_ACK; + if (status & I2C_INT_ARBITRATION_LOST) + i2c_dev->msg_err |= I2C_ERR_ARBITRATION_LOST; + complete(&i2c_dev->msg_complete); + goto err; + } + + if (i2c_dev->msg_read && (status & I2C_INT_RX_FIFO_DATA_REQ)) { + if (i2c_dev->msg_buf_remaining) + tegra_i2c_empty_rx_fifo(i2c_dev); + else + BUG(); + } + + if (!i2c_dev->msg_read && (status & I2C_INT_TX_FIFO_DATA_REQ)) { + if (i2c_dev->msg_buf_remaining) + tegra_i2c_fill_tx_fifo(i2c_dev); + else + tegra_i2c_mask_irq(i2c_dev, I2C_INT_TX_FIFO_DATA_REQ); + } + + if ((status & I2C_INT_PACKET_XFER_COMPLETE) && + !i2c_dev->msg_buf_remaining) + complete(&i2c_dev->msg_complete); + + i2c_writel(i2c_dev, status, I2C_INT_STATUS); + if (i2c_dev->is_dvc) + dvc_writel(i2c_dev, DVC_STATUS_I2C_DONE_INTR, DVC_STATUS); + return IRQ_HANDLED; +err: + /* An error occured, mask all interrupts */ + tegra_i2c_mask_irq(i2c_dev, I2C_INT_NO_ACK | I2C_INT_ARBITRATION_LOST | + I2C_INT_PACKET_XFER_COMPLETE | I2C_INT_TX_FIFO_DATA_REQ | + I2C_INT_RX_FIFO_DATA_REQ); + i2c_writel(i2c_dev, status, I2C_INT_STATUS); + return IRQ_HANDLED; +} + +static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev, + struct i2c_msg *msg, int stop) +{ + u32 packet_header; + u32 int_mask; + int ret; + + tegra_i2c_flush_fifos(i2c_dev); + i2c_writel(i2c_dev, 0xFF, I2C_INT_STATUS); + + if (msg->len == 0) + return -EINVAL; + + i2c_dev->msg_buf = msg->buf; + i2c_dev->msg_buf_remaining = msg->len; + i2c_dev->msg_err = I2C_ERR_NONE; + i2c_dev->msg_read = (msg->flags & I2C_M_RD); + INIT_COMPLETION(i2c_dev->msg_complete); + + packet_header = (0 << PACKET_HEADER0_HEADER_SIZE_SHIFT) | + PACKET_HEADER0_PROTOCOL_I2C | + (i2c_dev->cont_id << PACKET_HEADER0_CONT_ID_SHIFT) | + (1 << PACKET_HEADER0_PACKET_ID_SHIFT); + i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO); + + packet_header = msg->len - 1; + i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO); + + packet_header = msg->addr << I2C_HEADER_SLAVE_ADDR_SHIFT; + packet_header |= I2C_HEADER_IE_ENABLE; + if (msg->flags & I2C_M_TEN) + packet_header |= I2C_HEADER_10BIT_ADDR; + if (msg->flags & I2C_M_IGNORE_NAK) + packet_header |= I2C_HEADER_CONT_ON_NAK; + if (msg->flags & I2C_M_NOSTART) + packet_header |= I2C_HEADER_REPEAT_START; + if (msg->flags & I2C_M_RD) + packet_header |= I2C_HEADER_READ; + i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO); + + if (!(msg->flags & I2C_M_RD)) + tegra_i2c_fill_tx_fifo(i2c_dev); + + int_mask = I2C_INT_NO_ACK | I2C_INT_ARBITRATION_LOST; + if (msg->flags & I2C_M_RD) + int_mask |= I2C_INT_RX_FIFO_DATA_REQ; + else if (i2c_dev->msg_buf_remaining) + int_mask |= I2C_INT_TX_FIFO_DATA_REQ; + tegra_i2c_unmask_irq(i2c_dev, int_mask); + dev_dbg(i2c_dev->dev, "unmasked irq: %02x\n", + i2c_readl(i2c_dev, I2C_INT_MASK)); + + ret = wait_for_completion_timeout(&i2c_dev->msg_complete, TEGRA_I2C_TIMEOUT); + tegra_i2c_mask_irq(i2c_dev, int_mask); + + if (WARN_ON(ret == 0)) { + dev_err(i2c_dev->dev, "i2c transfer timed out\n"); + + tegra_i2c_init(i2c_dev); + return -ETIMEDOUT; + } + + dev_dbg(i2c_dev->dev, "transfer complete: %d %d %d\n", + ret, completion_done(&i2c_dev->msg_complete), i2c_dev->msg_err); + + if (likely(i2c_dev->msg_err == I2C_ERR_NONE)) + return 0; + + tegra_i2c_init(i2c_dev); + if (i2c_dev->msg_err == I2C_ERR_NO_ACK) { + if (msg->flags & I2C_M_IGNORE_NAK) + return 0; + return -EREMOTEIO; + } + + return -EIO; +} + +static int tegra_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], + int num) +{ + struct tegra_i2c_dev *i2c_dev = i2c_get_adapdata(adap); + int i; + int ret = 0; + + if (i2c_dev->is_suspended) + return -EBUSY; + + clk_enable(i2c_dev->clk); + for (i = 0; i < num; i++) { + int stop = (i == (num - 1)) ? 1 : 0; + ret = tegra_i2c_xfer_msg(i2c_dev, &msgs[i], stop); + if (ret) + break; + } + clk_disable(i2c_dev->clk); + return ret ?: i; +} + +static u32 tegra_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C; +} + +static const struct i2c_algorithm tegra_i2c_algo = { + .master_xfer = tegra_i2c_xfer, + .functionality = tegra_i2c_func, +}; + +static int tegra_i2c_probe(struct platform_device *pdev) +{ + struct tegra_i2c_dev *i2c_dev; + struct tegra_i2c_platform_data *pdata = pdev->dev.platform_data; + struct resource *res; + struct resource *iomem; + struct clk *clk; + struct clk *i2c_clk; + void *base; + int irq; + int ret = 0; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) { + dev_err(&pdev->dev, "no mem resource\n"); + return -EINVAL; + } + iomem = request_mem_region(res->start, resource_size(res), pdev->name); + if (!iomem) { + dev_err(&pdev->dev, "I2C region already claimed\n"); + return -EBUSY; + } + + base = ioremap(iomem->start, resource_size(iomem)); + if (!base) { + dev_err(&pdev->dev, "Cannot ioremap I2C region\n"); + return -ENOMEM; + } + + res = platform_get_resource(pdev, IORESOURCE_IRQ, 0); + if (!res) { + dev_err(&pdev->dev, "no irq resource\n"); + ret = -EINVAL; + goto err_iounmap; + } + irq = res->start; + + clk = clk_get(&pdev->dev, NULL); + if (IS_ERR(clk)) { + dev_err(&pdev->dev, "missing controller clock"); + ret = PTR_ERR(clk); + goto err_release_region; + } + + i2c_clk = clk_get(&pdev->dev, "i2c"); + if (IS_ERR(i2c_clk)) { + dev_err(&pdev->dev, "missing bus clock"); + ret = PTR_ERR(i2c_clk); + goto err_clk_put; + } + + i2c_dev = kzalloc(sizeof(struct tegra_i2c_dev), GFP_KERNEL); + if (!i2c_dev) { + ret = -ENOMEM; + goto err_i2c_clk_put; + } + + i2c_dev->base = base; + i2c_dev->clk = clk; + i2c_dev->i2c_clk = i2c_clk; + i2c_dev->iomem = iomem; + i2c_dev->adapter.algo = &tegra_i2c_algo; + i2c_dev->irq = irq; + i2c_dev->cont_id = pdev->id; + i2c_dev->dev = &pdev->dev; + i2c_dev->bus_clk_rate = pdata ? pdata->bus_clk_rate : 100000; + + if (pdev->id == 3) + i2c_dev->is_dvc = 1; + init_completion(&i2c_dev->msg_complete); + + platform_set_drvdata(pdev, i2c_dev); + + ret = tegra_i2c_init(i2c_dev); + if (ret) { + dev_err(&pdev->dev, "Failed to initialize i2c controller"); + goto err_free; + } + + ret = request_irq(i2c_dev->irq, tegra_i2c_isr, 0, pdev->name, i2c_dev); + if (ret) { + dev_err(&pdev->dev, "Failed to request irq %i\n", i2c_dev->irq); + goto err_free; + } + + clk_enable(i2c_dev->i2c_clk); + + i2c_set_adapdata(&i2c_dev->adapter, i2c_dev); + i2c_dev->adapter.owner = THIS_MODULE; + i2c_dev->adapter.class = I2C_CLASS_HWMON; + strlcpy(i2c_dev->adapter.name, "Tegra I2C adapter", + sizeof(i2c_dev->adapter.name)); + i2c_dev->adapter.algo = &tegra_i2c_algo; + i2c_dev->adapter.dev.parent = &pdev->dev; + i2c_dev->adapter.nr = pdev->id; + + ret = i2c_add_numbered_adapter(&i2c_dev->adapter); + if (ret) { + dev_err(&pdev->dev, "Failed to add I2C adapter\n"); + goto err_free_irq; + } + + return 0; +err_free_irq: + free_irq(i2c_dev->irq, i2c_dev); +err_free: + kfree(i2c_dev); +err_i2c_clk_put: + clk_put(i2c_clk); +err_clk_put: + clk_put(clk); +err_release_region: + release_mem_region(iomem->start, resource_size(iomem)); +err_iounmap: + iounmap(base); + return ret; +} + +static int tegra_i2c_remove(struct platform_device *pdev) +{ + struct tegra_i2c_dev *i2c_dev = platform_get_drvdata(pdev); + i2c_del_adapter(&i2c_dev->adapter); + free_irq(i2c_dev->irq, i2c_dev); + clk_put(i2c_dev->i2c_clk); + clk_put(i2c_dev->clk); + release_mem_region(i2c_dev->iomem->start, + resource_size(i2c_dev->iomem)); + iounmap(i2c_dev->base); + kfree(i2c_dev); + return 0; +} + +#ifdef CONFIG_PM +static int tegra_i2c_suspend(struct platform_device *pdev, pm_message_t state) +{ + struct tegra_i2c_dev *i2c_dev = platform_get_drvdata(pdev); + + i2c_lock_adapter(&i2c_dev->adapter); + i2c_dev->is_suspended = true; + i2c_unlock_adapter(&i2c_dev->adapter); + + return 0; +} + +static int tegra_i2c_resume(struct platform_device *pdev) +{ + struct tegra_i2c_dev *i2c_dev = platform_get_drvdata(pdev); + int ret; + + i2c_lock_adapter(&i2c_dev->adapter); + + ret = tegra_i2c_init(i2c_dev); + + if (ret) { + i2c_unlock_adapter(&i2c_dev->adapter); + return ret; + } + + i2c_dev->is_suspended = false; + + i2c_unlock_adapter(&i2c_dev->adapter); + + return 0; +} +#endif + +static struct platform_driver tegra_i2c_driver = { + .probe = tegra_i2c_probe, + .remove = tegra_i2c_remove, +#ifdef CONFIG_PM + .suspend = tegra_i2c_suspend, + .resume = tegra_i2c_resume, +#endif + .driver = { + .name = "tegra-i2c", + .owner = THIS_MODULE, + }, +}; + +static int __init tegra_i2c_init_driver(void) +{ + return platform_driver_register(&tegra_i2c_driver); +} + +static void __exit tegra_i2c_exit_driver(void) +{ + platform_driver_unregister(&tegra_i2c_driver); +} + +subsys_initcall(tegra_i2c_init_driver); +module_exit(tegra_i2c_exit_driver); + +MODULE_DESCRIPTION("nVidia Tegra2 I2C Bus Controller driver"); +MODULE_AUTHOR("Colin Cross"); +MODULE_LICENSE("GPL v2"); -- cgit v1.2.2 From a8da7fecb6010222fe495cc2b4330b99bca20c61 Mon Sep 17 00:00:00 2001 From: Wolfram Sang Date: Wed, 16 Feb 2011 13:39:16 +0100 Subject: i2c: add driver for Freescale i.MX28 Currently only supporting the PIOQUEUE-mode, because DMA-support for this platform is not yet in mainline. When it becomes available and support has been added to this driver, it will also be suitable for i.MX23 and STMP3xxx. Signed-off-by: Wolfram Sang Cc: Ben Dooks Cc: Shawn Guo Signed-off-by: Ben Dooks --- drivers/i2c/busses/Kconfig | 10 ++ drivers/i2c/busses/Makefile | 1 + drivers/i2c/busses/i2c-mxs.c | 412 +++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 423 insertions(+) create mode 100644 drivers/i2c/busses/i2c-mxs.c (limited to 'drivers/i2c/busses') diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig index 113505a6434e..e08e8356bdb5 100644 --- a/drivers/i2c/busses/Kconfig +++ b/drivers/i2c/busses/Kconfig @@ -452,6 +452,16 @@ config I2C_MV64XXX This driver can also be built as a module. If so, the module will be called i2c-mv64xxx. +config I2C_MXS + tristate "Freescale i.MX28 I2C interface" + depends on SOC_IMX28 + help + Say Y here if you want to use the I2C bus controller on + the Freescale i.MX28 processors. + + This driver can also be built as a module. If so, the module + will be called i2c-mxs. + config I2C_NOMADIK tristate "ST-Ericsson Nomadik/Ux500 I2C Controller" depends on PLAT_NOMADIK diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile index 9d2d0ec7fb23..77cf7e6447fc 100644 --- a/drivers/i2c/busses/Makefile +++ b/drivers/i2c/busses/Makefile @@ -43,6 +43,7 @@ obj-$(CONFIG_I2C_IOP3XX) += i2c-iop3xx.o obj-$(CONFIG_I2C_IXP2000) += i2c-ixp2000.o obj-$(CONFIG_I2C_MPC) += i2c-mpc.o obj-$(CONFIG_I2C_MV64XXX) += i2c-mv64xxx.o +obj-$(CONFIG_I2C_MXS) += i2c-mxs.o obj-$(CONFIG_I2C_NOMADIK) += i2c-nomadik.o obj-$(CONFIG_I2C_NUC900) += i2c-nuc900.o obj-$(CONFIG_I2C_OCORES) += i2c-ocores.o diff --git a/drivers/i2c/busses/i2c-mxs.c b/drivers/i2c/busses/i2c-mxs.c new file mode 100644 index 000000000000..8022e2390a5a --- /dev/null +++ b/drivers/i2c/busses/i2c-mxs.c @@ -0,0 +1,412 @@ +/* + * Freescale MXS I2C bus driver + * + * Copyright (C) 2011 Wolfram Sang, Pengutronix e.K. + * + * based on a (non-working) driver which was: + * + * Copyright (C) 2009-2010 Freescale Semiconductor, Inc. All Rights Reserved. + * + * TODO: add dma-support if platform-support for it is available + * + * 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; either version 2 of the License, or + * (at your option) any later version. + * + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +#define DRIVER_NAME "mxs-i2c" + +#define MXS_I2C_CTRL0 (0x00) +#define MXS_I2C_CTRL0_SET (0x04) + +#define MXS_I2C_CTRL0_SFTRST 0x80000000 +#define MXS_I2C_CTRL0_SEND_NAK_ON_LAST 0x02000000 +#define MXS_I2C_CTRL0_RETAIN_CLOCK 0x00200000 +#define MXS_I2C_CTRL0_POST_SEND_STOP 0x00100000 +#define MXS_I2C_CTRL0_PRE_SEND_START 0x00080000 +#define MXS_I2C_CTRL0_MASTER_MODE 0x00020000 +#define MXS_I2C_CTRL0_DIRECTION 0x00010000 +#define MXS_I2C_CTRL0_XFER_COUNT(v) ((v) & 0x0000FFFF) + +#define MXS_I2C_CTRL1 (0x40) +#define MXS_I2C_CTRL1_SET (0x44) +#define MXS_I2C_CTRL1_CLR (0x48) + +#define MXS_I2C_CTRL1_BUS_FREE_IRQ 0x80 +#define MXS_I2C_CTRL1_DATA_ENGINE_CMPLT_IRQ 0x40 +#define MXS_I2C_CTRL1_NO_SLAVE_ACK_IRQ 0x20 +#define MXS_I2C_CTRL1_OVERSIZE_XFER_TERM_IRQ 0x10 +#define MXS_I2C_CTRL1_EARLY_TERM_IRQ 0x08 +#define MXS_I2C_CTRL1_MASTER_LOSS_IRQ 0x04 +#define MXS_I2C_CTRL1_SLAVE_STOP_IRQ 0x02 +#define MXS_I2C_CTRL1_SLAVE_IRQ 0x01 + +#define MXS_I2C_IRQ_MASK (MXS_I2C_CTRL1_DATA_ENGINE_CMPLT_IRQ | \ + MXS_I2C_CTRL1_NO_SLAVE_ACK_IRQ | \ + MXS_I2C_CTRL1_EARLY_TERM_IRQ | \ + MXS_I2C_CTRL1_MASTER_LOSS_IRQ | \ + MXS_I2C_CTRL1_SLAVE_STOP_IRQ | \ + MXS_I2C_CTRL1_SLAVE_IRQ) + +#define MXS_I2C_QUEUECTRL (0x60) +#define MXS_I2C_QUEUECTRL_SET (0x64) +#define MXS_I2C_QUEUECTRL_CLR (0x68) + +#define MXS_I2C_QUEUECTRL_QUEUE_RUN 0x20 +#define MXS_I2C_QUEUECTRL_PIO_QUEUE_MODE 0x04 + +#define MXS_I2C_QUEUESTAT (0x70) +#define MXS_I2C_QUEUESTAT_RD_QUEUE_EMPTY 0x00002000 + +#define MXS_I2C_QUEUECMD (0x80) + +#define MXS_I2C_QUEUEDATA (0x90) + +#define MXS_I2C_DATA (0xa0) + + +#define MXS_CMD_I2C_SELECT (MXS_I2C_CTRL0_RETAIN_CLOCK | \ + MXS_I2C_CTRL0_PRE_SEND_START | \ + MXS_I2C_CTRL0_MASTER_MODE | \ + MXS_I2C_CTRL0_DIRECTION | \ + MXS_I2C_CTRL0_XFER_COUNT(1)) + +#define MXS_CMD_I2C_WRITE (MXS_I2C_CTRL0_PRE_SEND_START | \ + MXS_I2C_CTRL0_MASTER_MODE | \ + MXS_I2C_CTRL0_DIRECTION) + +#define MXS_CMD_I2C_READ (MXS_I2C_CTRL0_SEND_NAK_ON_LAST | \ + MXS_I2C_CTRL0_MASTER_MODE) + +/** + * struct mxs_i2c_dev - per device, private MXS-I2C data + * + * @dev: driver model device node + * @regs: IO registers pointer + * @cmd_complete: completion object for transaction wait + * @cmd_err: error code for last transaction + * @adapter: i2c subsystem adapter node + */ +struct mxs_i2c_dev { + struct device *dev; + void __iomem *regs; + struct completion cmd_complete; + u32 cmd_err; + struct i2c_adapter adapter; +}; + +/* + * TODO: check if calls to here are really needed. If not, we could get rid of + * mxs_reset_block and the mach-dependency. Needs an I2C analyzer, probably. + */ +static void mxs_i2c_reset(struct mxs_i2c_dev *i2c) +{ + mxs_reset_block(i2c->regs); + writel(MXS_I2C_IRQ_MASK << 8, i2c->regs + MXS_I2C_CTRL1_SET); +} + +static void mxs_i2c_pioq_setup_read(struct mxs_i2c_dev *i2c, u8 addr, int len, + int flags) +{ + u32 data; + + writel(MXS_CMD_I2C_SELECT, i2c->regs + MXS_I2C_QUEUECMD); + + data = (addr << 1) | I2C_SMBUS_READ; + writel(data, i2c->regs + MXS_I2C_DATA); + + data = MXS_CMD_I2C_READ | MXS_I2C_CTRL0_XFER_COUNT(len) | flags; + writel(data, i2c->regs + MXS_I2C_QUEUECMD); +} + +static void mxs_i2c_pioq_setup_write(struct mxs_i2c_dev *i2c, + u8 addr, u8 *buf, int len, int flags) +{ + u32 data; + int i, shifts_left; + + data = MXS_CMD_I2C_WRITE | MXS_I2C_CTRL0_XFER_COUNT(len + 1) | flags; + writel(data, i2c->regs + MXS_I2C_QUEUECMD); + + /* + * We have to copy the slave address (u8) and buffer (arbitrary number + * of u8) into the data register (u32). To achieve that, the u8 are put + * into the MSBs of 'data' which is then shifted for the next u8. When + * apropriate, 'data' is written to MXS_I2C_DATA. So, the first u32 + * looks like this: + * + * 3 2 1 0 + * 10987654|32109876|54321098|76543210 + * --------+--------+--------+-------- + * buffer+2|buffer+1|buffer+0|slave_addr + */ + + data = ((addr << 1) | I2C_SMBUS_WRITE) << 24; + + for (i = 0; i < len; i++) { + data >>= 8; + data |= buf[i] << 24; + if ((i & 3) == 2) + writel(data, i2c->regs + MXS_I2C_DATA); + } + + /* Write out the remaining bytes if any */ + shifts_left = 24 - (i & 3) * 8; + if (shifts_left) + writel(data >> shifts_left, i2c->regs + MXS_I2C_DATA); +} + +/* + * TODO: should be replaceable with a waitqueue and RD_QUEUE_IRQ (setting the + * rd_threshold to 1). Couldn't get this to work, though. + */ +static int mxs_i2c_wait_for_data(struct mxs_i2c_dev *i2c) +{ + unsigned long timeout = jiffies + msecs_to_jiffies(1000); + + while (readl(i2c->regs + MXS_I2C_QUEUESTAT) + & MXS_I2C_QUEUESTAT_RD_QUEUE_EMPTY) { + if (time_after(jiffies, timeout)) + return -ETIMEDOUT; + cond_resched(); + } + + return 0; +} + +static int mxs_i2c_finish_read(struct mxs_i2c_dev *i2c, u8 *buf, int len) +{ + u32 data; + int i; + + for (i = 0; i < len; i++) { + if ((i & 3) == 0) { + if (mxs_i2c_wait_for_data(i2c)) + return -ETIMEDOUT; + data = readl(i2c->regs + MXS_I2C_QUEUEDATA); + } + buf[i] = data & 0xff; + data >>= 8; + } + + return 0; +} + +/* + * Low level master read/write transaction. + */ +static int mxs_i2c_xfer_msg(struct i2c_adapter *adap, struct i2c_msg *msg, + int stop) +{ + struct mxs_i2c_dev *i2c = i2c_get_adapdata(adap); + int ret; + int flags; + + init_completion(&i2c->cmd_complete); + + dev_dbg(i2c->dev, "addr: 0x%04x, len: %d, flags: 0x%x, stop: %d\n", + msg->addr, msg->len, msg->flags, stop); + + if (msg->len == 0) + return -EINVAL; + + flags = stop ? MXS_I2C_CTRL0_POST_SEND_STOP : 0; + + if (msg->flags & I2C_M_RD) + mxs_i2c_pioq_setup_read(i2c, msg->addr, msg->len, flags); + else + mxs_i2c_pioq_setup_write(i2c, msg->addr, msg->buf, msg->len, + flags); + + writel(MXS_I2C_QUEUECTRL_QUEUE_RUN, + i2c->regs + MXS_I2C_QUEUECTRL_SET); + + ret = wait_for_completion_timeout(&i2c->cmd_complete, + msecs_to_jiffies(1000)); + if (ret == 0) + goto timeout; + + if ((!i2c->cmd_err) && (msg->flags & I2C_M_RD)) { + ret = mxs_i2c_finish_read(i2c, msg->buf, msg->len); + if (ret) + goto timeout; + } + + if (i2c->cmd_err == -ENXIO) + mxs_i2c_reset(i2c); + + dev_dbg(i2c->dev, "Done with err=%d\n", i2c->cmd_err); + + return i2c->cmd_err; + +timeout: + dev_dbg(i2c->dev, "Timeout!\n"); + mxs_i2c_reset(i2c); + return -ETIMEDOUT; +} + +static int mxs_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], + int num) +{ + int i; + int err; + + for (i = 0; i < num; i++) { + err = mxs_i2c_xfer_msg(adap, &msgs[i], i == (num - 1)); + if (err) + return err; + } + + return num; +} + +static u32 mxs_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK); +} + +static irqreturn_t mxs_i2c_isr(int this_irq, void *dev_id) +{ + struct mxs_i2c_dev *i2c = dev_id; + u32 stat = readl(i2c->regs + MXS_I2C_CTRL1) & MXS_I2C_IRQ_MASK; + + if (!stat) + return IRQ_NONE; + + if (stat & MXS_I2C_CTRL1_NO_SLAVE_ACK_IRQ) + i2c->cmd_err = -ENXIO; + else if (stat & (MXS_I2C_CTRL1_EARLY_TERM_IRQ | + MXS_I2C_CTRL1_MASTER_LOSS_IRQ | + MXS_I2C_CTRL1_SLAVE_STOP_IRQ | MXS_I2C_CTRL1_SLAVE_IRQ)) + /* MXS_I2C_CTRL1_OVERSIZE_XFER_TERM_IRQ is only for slaves */ + i2c->cmd_err = -EIO; + else + i2c->cmd_err = 0; + + complete(&i2c->cmd_complete); + + writel(stat, i2c->regs + MXS_I2C_CTRL1_CLR); + return IRQ_HANDLED; +} + +static const struct i2c_algorithm mxs_i2c_algo = { + .master_xfer = mxs_i2c_xfer, + .functionality = mxs_i2c_func, +}; + +static int __devinit mxs_i2c_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct mxs_i2c_dev *i2c; + struct i2c_adapter *adap; + struct resource *res; + resource_size_t res_size; + int err, irq; + + i2c = devm_kzalloc(dev, sizeof(struct mxs_i2c_dev), GFP_KERNEL); + if (!i2c) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) + return -ENOENT; + + res_size = resource_size(res); + if (!devm_request_mem_region(dev, res->start, res_size, res->name)) + return -EBUSY; + + i2c->regs = devm_ioremap_nocache(dev, res->start, res_size); + if (!i2c->regs) + return -EBUSY; + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + err = devm_request_irq(dev, irq, mxs_i2c_isr, 0, dev_name(dev), i2c); + if (err) + return err; + + i2c->dev = dev; + platform_set_drvdata(pdev, i2c); + + /* Do reset to enforce correct startup after pinmuxing */ + mxs_i2c_reset(i2c); + writel(MXS_I2C_QUEUECTRL_PIO_QUEUE_MODE, + i2c->regs + MXS_I2C_QUEUECTRL_SET); + + adap = &i2c->adapter; + strlcpy(adap->name, "MXS I2C adapter", sizeof(adap->name)); + adap->owner = THIS_MODULE; + adap->algo = &mxs_i2c_algo; + adap->dev.parent = dev; + adap->nr = pdev->id; + i2c_set_adapdata(adap, i2c); + err = i2c_add_numbered_adapter(adap); + if (err) { + dev_err(dev, "Failed to add adapter (%d)\n", err); + writel(MXS_I2C_CTRL0_SFTRST, + i2c->regs + MXS_I2C_CTRL0_SET); + return err; + } + + return 0; +} + +static int __devexit mxs_i2c_remove(struct platform_device *pdev) +{ + struct mxs_i2c_dev *i2c = platform_get_drvdata(pdev); + int ret; + + ret = i2c_del_adapter(&i2c->adapter); + if (ret) + return -EBUSY; + + writel(MXS_I2C_QUEUECTRL_QUEUE_RUN, + i2c->regs + MXS_I2C_QUEUECTRL_CLR); + writel(MXS_I2C_CTRL0_SFTRST, i2c->regs + MXS_I2C_CTRL0_SET); + + platform_set_drvdata(pdev, NULL); + + return 0; +} + +static struct platform_driver mxs_i2c_driver = { + .driver = { + .name = DRIVER_NAME, + .owner = THIS_MODULE, + }, + .remove = __devexit_p(mxs_i2c_remove), +}; + +static int __init mxs_i2c_init(void) +{ + return platform_driver_probe(&mxs_i2c_driver, mxs_i2c_probe); +} +subsys_initcall(mxs_i2c_init); + +static void __exit mxs_i2c_exit(void) +{ + platform_driver_unregister(&mxs_i2c_driver); +} +module_exit(mxs_i2c_exit); + +MODULE_AUTHOR("Wolfram Sang "); +MODULE_DESCRIPTION("MXS I2C Bus Driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:" DRIVER_NAME); -- cgit v1.2.2 From 0724d46417545aa3035d88fb8885dffe68817a8c Mon Sep 17 00:00:00 2001 From: Kumar Gala Date: Tue, 15 Mar 2011 11:02:43 -0500 Subject: i2c-mpc: Add support for 64bit system Currently i2c-mpc supports 32bit system only, this modification makes it supported on both 32-bit and 64-bit systems. The P5020 is the first 64-bit PPC system with the i2c-mpc controller. Based in patch from Xulei Signed-off-by: Kumar Gala Signed-off-by: Ben Dooks --- drivers/i2c/busses/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/i2c/busses') diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig index 113505a6434e..107d5c201b6b 100644 --- a/drivers/i2c/busses/Kconfig +++ b/drivers/i2c/busses/Kconfig @@ -433,7 +433,7 @@ config I2C_IXP2000 config I2C_MPC tristate "MPC107/824x/85xx/512x/52xx/83xx/86xx" - depends on PPC32 + depends on PPC help If you say yes to this option, support will be included for the built-in I2C interface on the MPC107, Tsi107, MPC512x, MPC52xx, -- cgit v1.2.2