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path: root/drivers/i2c/busses/i2c-tegra.c
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Diffstat (limited to 'drivers/i2c/busses/i2c-tegra.c')
-rw-r--r--drivers/i2c/busses/i2c-tegra.c154
1 files changed, 97 insertions, 57 deletions
diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index 7b38877ffec..f1bb2fc0679 100644
--- a/drivers/i2c/busses/i2c-tegra.c
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -25,15 +25,12 @@
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/slab.h>
-#include <linux/i2c-tegra.h>
-#include <linux/of_i2c.h>
#include <linux/of_device.h>
#include <linux/module.h>
+#include <linux/reset.h>
#include <asm/unaligned.h>
-#include <mach/clk.h>
-
#define TEGRA_I2C_TIMEOUT (msecs_to_jiffies(1000))
#define BYTES_PER_FIFO_WORD 4
@@ -71,6 +68,8 @@
#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)
@@ -117,10 +116,23 @@ 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;
};
/**
@@ -148,6 +160,7 @@ struct tegra_i2c_dev {
struct i2c_adapter adapter;
struct clk *div_clk;
struct clk *fast_clk;
+ struct reset_control *rst;
void __iomem *base;
int cont_id;
int irq;
@@ -158,7 +171,7 @@ struct tegra_i2c_dev {
u8 *msg_buf;
size_t msg_buf_remaining;
int msg_read;
- unsigned long bus_clk_rate;
+ u32 bus_clk_rate;
bool is_suspended;
};
@@ -366,11 +379,13 @@ 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) {
@@ -384,19 +399,26 @@ 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);
+ err = tegra_i2c_clock_enable(i2c_dev);
+ if (err < 0) {
+ dev_err(i2c_dev->dev, "Clock enable failed %d\n", err);
+ return err;
+ }
- tegra_periph_reset_assert(i2c_dev->div_clk);
+ reset_control_assert(i2c_dev->rst);
udelay(2);
- tegra_periph_reset_deassert(i2c_dev->div_clk);
+ reset_control_deassert(i2c_dev->rst);
if (i2c_dev->is_dvc)
tegra_dvc_init(i2c_dev);
@@ -405,7 +427,15 @@ 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);
@@ -515,7 +545,7 @@ static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev,
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);
+ reinit_completion(&i2c_dev->msg_complete);
packet_header = (0 << PACKET_HEADER0_HEADER_SIZE_SHIFT) |
PACKET_HEADER0_PROTOCOL_I2C |
@@ -547,6 +577,8 @@ 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)
@@ -558,7 +590,7 @@ 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);
@@ -599,7 +631,12 @@ static int tegra_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[],
if (i2c_dev->is_suspended)
return -EBUSY;
- tegra_i2c_clock_enable(i2c_dev);
+ ret = tegra_i2c_clock_enable(i2c_dev);
+ if (ret < 0) {
+ dev_err(i2c_dev->dev, "Clock enable failed %d\n", ret);
+ return ret;
+ }
+
for (i = 0; i < num; i++) {
enum msg_end_type end_type = MSG_END_STOP;
if (i < (num - 1)) {
@@ -634,46 +671,52 @@ 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, },
{},
};
MODULE_DEVICE_TABLE(of, tegra_i2c_of_match);
-#endif
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 clk *div_clk;
struct clk *fast_clk;
- const unsigned int *prop;
void __iomem *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;
- }
-
- base = devm_request_and_ioremap(&pdev->dev, res);
- if (!base) {
- dev_err(&pdev->dev, "Cannot request/ioremap I2C registers\n");
- return -EADDRNOTAVAIL;
- }
+ base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(base))
+ return PTR_ERR(base);
res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
if (!res) {
@@ -688,43 +731,33 @@ 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");
+ if (!i2c_dev)
return -ENOMEM;
- }
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;
i2c_dev->dev = &pdev->dev;
- i2c_dev->bus_clk_rate = 100000; /* default clock rate */
- if (pdata) {
- i2c_dev->bus_clk_rate = pdata->bus_clk_rate;
-
- } else if (i2c_dev->dev->of_node) { /* if there is a device tree node ... */
- prop = of_get_property(i2c_dev->dev->of_node,
- "clock-frequency", NULL);
- if (prop)
- i2c_dev->bus_clk_rate = be32_to_cpup(prop);
+ i2c_dev->rst = devm_reset_control_get(&pdev->dev, "i2c");
+ if (IS_ERR(i2c_dev->rst)) {
+ dev_err(&pdev->dev, "missing controller reset");
+ return PTR_ERR(i2c_dev->rst);
}
+ ret = of_property_read_u32(i2c_dev->dev->of_node, "clock-frequency",
+ &i2c_dev->bus_clk_rate);
+ if (ret)
+ i2c_dev->bus_clk_rate = 100000; /* default clock rate */
+
i2c_dev->hw = &tegra20_i2c_hw;
if (pdev->dev.of_node) {
const struct of_device_id *match;
- match = of_match_device(of_match_ptr(tegra_i2c_of_match),
- &pdev->dev);
+ match = of_match_device(tegra_i2c_of_match, &pdev->dev);
i2c_dev->hw = match->data;
i2c_dev->is_dvc = of_device_is_compatible(pdev->dev.of_node,
"nvidia,tegra20-i2c-dvc");
@@ -733,6 +766,15 @@ 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);
@@ -750,7 +792,7 @@ static int tegra_i2c_probe(struct platform_device *pdev)
i2c_set_adapdata(&i2c_dev->adapter, i2c_dev);
i2c_dev->adapter.owner = THIS_MODULE;
- i2c_dev->adapter.class = I2C_CLASS_HWMON;
+ i2c_dev->adapter.class = I2C_CLASS_HWMON | I2C_CLASS_DEPRECATED;
strlcpy(i2c_dev->adapter.name, "Tegra I2C adapter",
sizeof(i2c_dev->adapter.name));
i2c_dev->adapter.algo = &tegra_i2c_algo;
@@ -764,8 +806,6 @@ static int tegra_i2c_probe(struct platform_device *pdev)
return ret;
}
- of_i2c_register_devices(&i2c_dev->adapter);
-
return 0;
}
@@ -821,7 +861,7 @@ static struct platform_driver tegra_i2c_driver = {
.driver = {
.name = "tegra-i2c",
.owner = THIS_MODULE,
- .of_match_table = of_match_ptr(tegra_i2c_of_match),
+ .of_match_table = tegra_i2c_of_match,
.pm = TEGRA_I2C_PM,
},
};