diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-tegra.c')
| -rw-r--r-- | drivers/i2c/busses/i2c-tegra.c | 154 |
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, }, }; |
