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authorLinus Torvalds <torvalds@linux-foundation.org>2013-02-26 09:41:53 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2013-02-26 09:41:53 -0800
commit52caa59ed335616c5254adff7911465a57ed9f14 (patch)
treede0a1e91850c9e439e82f83f228d89fee3b90b09 /drivers/i2c/busses/i2c-tegra.c
parent4c8c225abf972ce422c241579ce1d4d27eaeb166 (diff)
parent55827f4aa6442ddd1d6a4e1e32f2f457eb113c22 (diff)
downloadop-kernel-dev-52caa59ed335616c5254adff7911465a57ed9f14.zip
op-kernel-dev-52caa59ed335616c5254adff7911465a57ed9f14.tar.gz
Merge branch 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang: "Highlights: - new drivers for Intel ismt & Broadcom bcm2835 - a number of drivers got support for more variants and mostly got cleaned up on the way (sis630, i801, at91, tegra, designware) - i2c got rid of all *_set_drvdata(..., NULL) on remove/probe failure - removed the i2c_smbus_process_call from the core since there are no users - mxs can now switch between PIO and DMA depending on the message size and the bus speed can now be arbitrary In addition, there is the usual bunch of fixes, cleanups, devm_* conversions, etc" Fixed conflict (and buggy devm_* conversion) in i2c-s3c2410.c * 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (39 commits) i2c: Remove unneeded xxx_set_drvdata(..., NULL) calls i2c: pxa: remove incorrect __exit annotations i2c: ocores: Fix pointer to integer cast warning i2c: tegra: remove warning dump if timeout happen in transfer i2c: fix i2c-ismt.c printk format warning i2c: i801: Add Device IDs for Intel Wellsburg PCH i2c: add bcm2835 driver i2c: ismt: Add Seth and Myself as maintainers i2c: sis630: checkpatch cleanup i2c: sis630: display unsigned hex i2c: sis630: use hex to constants for SMBus commands i2c: sis630: fix behavior after collision i2c: sis630: clear sticky bits i2c: sis630: Add SIS964 support i2c: isch: Add module parameter for backbone clock rate if divider is unset i2c: at91: fix unsed variable warning when building with !CONFIG_OF i2c: Adding support for Intel iSMT SMBus 2.0 host controller i2c: sh_mobile: don't send a stop condition by default inside transfers i2c: sh_mobile: eliminate an open-coded "goto" loop i2c: sh_mobile: fix timeout error handling ...
Diffstat (limited to 'drivers/i2c/busses/i2c-tegra.c')
-rw-r--r--drivers/i2c/busses/i2c-tegra.c79
1 files changed, 64 insertions, 15 deletions
diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index f0d9923..36704e3 100644
--- a/drivers/i2c/busses/i2c-tegra.c
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -70,6 +70,8 @@
#define I2C_INT_TX_FIFO_DATA_REQ (1<<1)
#define I2C_INT_RX_FIFO_DATA_REQ (1<<0)
#define I2C_CLK_DIVISOR 0x06c
+#define I2C_CLK_DIVISOR_STD_FAST_MODE_SHIFT 16
+#define I2C_CLK_MULTIPLIER_STD_FAST_MODE 8
#define DVC_CTRL_REG1 0x000
#define DVC_CTRL_REG1_INTR_EN (1<<10)
@@ -116,10 +118,23 @@ enum msg_end_type {
/**
* struct tegra_i2c_hw_feature : Different HW support on Tegra
* @has_continue_xfer_support: Continue transfer supports.
+ * @has_per_pkt_xfer_complete_irq: Has enable/disable capability for transfer
+ * complete interrupt per packet basis.
+ * @has_single_clk_source: The i2c controller has single clock source. Tegra30
+ * and earlier Socs has two clock sources i.e. div-clk and
+ * fast-clk.
+ * @clk_divisor_hs_mode: Clock divisor in HS mode.
+ * @clk_divisor_std_fast_mode: Clock divisor in standard/fast mode. It is
+ * applicable if there is no fast clock source i.e. single clock
+ * source.
*/
struct tegra_i2c_hw_feature {
bool has_continue_xfer_support;
+ bool has_per_pkt_xfer_complete_irq;
+ bool has_single_clk_source;
+ int clk_divisor_hs_mode;
+ int clk_divisor_std_fast_mode;
};
/**
@@ -365,11 +380,13 @@ static void tegra_dvc_init(struct tegra_i2c_dev *i2c_dev)
static inline int tegra_i2c_clock_enable(struct tegra_i2c_dev *i2c_dev)
{
int ret;
- ret = clk_prepare_enable(i2c_dev->fast_clk);
- if (ret < 0) {
- dev_err(i2c_dev->dev,
- "Enabling fast clk failed, err %d\n", ret);
- return ret;
+ if (!i2c_dev->hw->has_single_clk_source) {
+ ret = clk_prepare_enable(i2c_dev->fast_clk);
+ if (ret < 0) {
+ dev_err(i2c_dev->dev,
+ "Enabling fast clk failed, err %d\n", ret);
+ return ret;
+ }
}
ret = clk_prepare_enable(i2c_dev->div_clk);
if (ret < 0) {
@@ -383,13 +400,16 @@ static inline int tegra_i2c_clock_enable(struct tegra_i2c_dev *i2c_dev)
static inline void tegra_i2c_clock_disable(struct tegra_i2c_dev *i2c_dev)
{
clk_disable_unprepare(i2c_dev->div_clk);
- clk_disable_unprepare(i2c_dev->fast_clk);
+ if (!i2c_dev->hw->has_single_clk_source)
+ clk_disable_unprepare(i2c_dev->fast_clk);
}
static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev)
{
u32 val;
int err = 0;
+ int clk_multiplier = I2C_CLK_MULTIPLIER_STD_FAST_MODE;
+ u32 clk_divisor;
tegra_i2c_clock_enable(i2c_dev);
@@ -404,7 +424,15 @@ static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev)
(0x2 << I2C_CNFG_DEBOUNCE_CNT_SHIFT);
i2c_writel(i2c_dev, val, I2C_CNFG);
i2c_writel(i2c_dev, 0, I2C_INT_MASK);
- clk_set_rate(i2c_dev->div_clk, i2c_dev->bus_clk_rate * 8);
+
+ clk_multiplier *= (i2c_dev->hw->clk_divisor_std_fast_mode + 1);
+ clk_set_rate(i2c_dev->div_clk, i2c_dev->bus_clk_rate * clk_multiplier);
+
+ /* Make sure clock divisor programmed correctly */
+ clk_divisor = i2c_dev->hw->clk_divisor_hs_mode;
+ clk_divisor |= i2c_dev->hw->clk_divisor_std_fast_mode <<
+ I2C_CLK_DIVISOR_STD_FAST_MODE_SHIFT;
+ i2c_writel(i2c_dev, clk_divisor, I2C_CLK_DIVISOR);
if (!i2c_dev->is_dvc) {
u32 sl_cfg = i2c_readl(i2c_dev, I2C_SL_CNFG);
@@ -546,6 +574,8 @@ static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev,
tegra_i2c_fill_tx_fifo(i2c_dev);
int_mask = I2C_INT_NO_ACK | I2C_INT_ARBITRATION_LOST;
+ if (i2c_dev->hw->has_per_pkt_xfer_complete_irq)
+ int_mask |= I2C_INT_PACKET_XFER_COMPLETE;
if (msg->flags & I2C_M_RD)
int_mask |= I2C_INT_RX_FIFO_DATA_REQ;
else if (i2c_dev->msg_buf_remaining)
@@ -557,7 +587,7 @@ static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev,
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)) {
+ if (ret == 0) {
dev_err(i2c_dev->dev, "i2c transfer timed out\n");
tegra_i2c_init(i2c_dev);
@@ -633,15 +663,32 @@ static const struct i2c_algorithm tegra_i2c_algo = {
static const struct tegra_i2c_hw_feature tegra20_i2c_hw = {
.has_continue_xfer_support = false,
+ .has_per_pkt_xfer_complete_irq = false,
+ .has_single_clk_source = false,
+ .clk_divisor_hs_mode = 3,
+ .clk_divisor_std_fast_mode = 0,
};
static const struct tegra_i2c_hw_feature tegra30_i2c_hw = {
.has_continue_xfer_support = true,
+ .has_per_pkt_xfer_complete_irq = false,
+ .has_single_clk_source = false,
+ .clk_divisor_hs_mode = 3,
+ .clk_divisor_std_fast_mode = 0,
+};
+
+static const struct tegra_i2c_hw_feature tegra114_i2c_hw = {
+ .has_continue_xfer_support = true,
+ .has_per_pkt_xfer_complete_irq = true,
+ .has_single_clk_source = true,
+ .clk_divisor_hs_mode = 1,
+ .clk_divisor_std_fast_mode = 0x19,
};
#if defined(CONFIG_OF)
/* Match table for of_platform binding */
static const struct of_device_id tegra_i2c_of_match[] = {
+ { .compatible = "nvidia,tegra114-i2c", .data = &tegra114_i2c_hw, },
{ .compatible = "nvidia,tegra30-i2c", .data = &tegra30_i2c_hw, },
{ .compatible = "nvidia,tegra20-i2c", .data = &tegra20_i2c_hw, },
{ .compatible = "nvidia,tegra20-i2c-dvc", .data = &tegra20_i2c_hw, },
@@ -685,12 +732,6 @@ static int tegra_i2c_probe(struct platform_device *pdev)
return PTR_ERR(div_clk);
}
- fast_clk = devm_clk_get(&pdev->dev, "fast-clk");
- if (IS_ERR(fast_clk)) {
- dev_err(&pdev->dev, "missing bus clock");
- return PTR_ERR(fast_clk);
- }
-
i2c_dev = devm_kzalloc(&pdev->dev, sizeof(*i2c_dev), GFP_KERNEL);
if (!i2c_dev) {
dev_err(&pdev->dev, "Could not allocate struct tegra_i2c_dev");
@@ -699,7 +740,6 @@ static int tegra_i2c_probe(struct platform_device *pdev)
i2c_dev->base = base;
i2c_dev->div_clk = div_clk;
- i2c_dev->fast_clk = fast_clk;
i2c_dev->adapter.algo = &tegra_i2c_algo;
i2c_dev->irq = irq;
i2c_dev->cont_id = pdev->id;
@@ -730,6 +770,15 @@ static int tegra_i2c_probe(struct platform_device *pdev)
}
init_completion(&i2c_dev->msg_complete);
+ if (!i2c_dev->hw->has_single_clk_source) {
+ fast_clk = devm_clk_get(&pdev->dev, "fast-clk");
+ if (IS_ERR(fast_clk)) {
+ dev_err(&pdev->dev, "missing fast clock");
+ return PTR_ERR(fast_clk);
+ }
+ i2c_dev->fast_clk = fast_clk;
+ }
+
platform_set_drvdata(pdev, i2c_dev);
ret = tegra_i2c_init(i2c_dev);
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