diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-tegra.c')
| -rw-r--r-- | drivers/i2c/busses/i2c-tegra.c | 740 |
1 files changed, 647 insertions, 93 deletions
diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c index c77adbbea0c7..ebaa78d17d6e 100644 --- a/drivers/i2c/busses/i2c-tegra.c +++ b/drivers/i2c/busses/i2c-tegra.c @@ -6,26 +6,24 @@ * Author: Colin Cross <ccross@android.com> */ -#include <linux/kernel.h> -#include <linux/init.h> -#include <linux/platform_device.h> #include <linux/clk.h> +#include <linux/delay.h> +#include <linux/dmaengine.h> +#include <linux/dma-mapping.h> #include <linux/err.h> #include <linux/i2c.h> -#include <linux/io.h> +#include <linux/init.h> #include <linux/interrupt.h> -#include <linux/delay.h> -#include <linux/slab.h> -#include <linux/of_device.h> +#include <linux/io.h> +#include <linux/iopoll.h> +#include <linux/kernel.h> #include <linux/module.h> -#include <linux/reset.h> +#include <linux/of_device.h> #include <linux/pinctrl/consumer.h> +#include <linux/platform_device.h> #include <linux/pm_runtime.h> -#include <linux/iopoll.h> - -#include <asm/unaligned.h> +#include <linux/reset.h> -#define TEGRA_I2C_TIMEOUT (msecs_to_jiffies(1000)) #define BYTES_PER_FIFO_WORD 4 #define I2C_CNFG 0x000 @@ -45,8 +43,8 @@ #define I2C_FIFO_CONTROL 0x05c #define I2C_FIFO_CONTROL_TX_FLUSH BIT(1) #define I2C_FIFO_CONTROL_RX_FLUSH BIT(0) -#define I2C_FIFO_CONTROL_TX_TRIG_SHIFT 5 -#define I2C_FIFO_CONTROL_RX_TRIG_SHIFT 2 +#define I2C_FIFO_CONTROL_TX_TRIG(x) (((x) - 1) << 5) +#define I2C_FIFO_CONTROL_RX_TRIG(x) (((x) - 1) << 2) #define I2C_FIFO_STATUS 0x060 #define I2C_FIFO_STATUS_TX_MASK 0xF0 #define I2C_FIFO_STATUS_TX_SHIFT 4 @@ -54,6 +52,7 @@ #define I2C_FIFO_STATUS_RX_SHIFT 0 #define I2C_INT_MASK 0x064 #define I2C_INT_STATUS 0x068 +#define I2C_INT_BUS_CLR_DONE BIT(11) #define I2C_INT_PACKET_XFER_COMPLETE BIT(7) #define I2C_INT_ALL_PACKETS_XFER_COMPLETE BIT(6) #define I2C_INT_TX_FIFO_OVERFLOW BIT(5) @@ -96,6 +95,15 @@ #define I2C_HEADER_MASTER_ADDR_SHIFT 12 #define I2C_HEADER_SLAVE_ADDR_SHIFT 1 +#define I2C_BUS_CLEAR_CNFG 0x084 +#define I2C_BC_SCLK_THRESHOLD 9 +#define I2C_BC_SCLK_THRESHOLD_SHIFT 16 +#define I2C_BC_STOP_COND BIT(2) +#define I2C_BC_TERMINATE BIT(1) +#define I2C_BC_ENABLE BIT(0) +#define I2C_BUS_CLEAR_STATUS 0x088 +#define I2C_BC_STATUS BIT(0) + #define I2C_CONFIG_LOAD 0x08C #define I2C_MSTR_CONFIG_LOAD BIT(0) #define I2C_SLV_CONFIG_LOAD BIT(1) @@ -118,6 +126,25 @@ #define I2C_MST_FIFO_STATUS_TX_MASK 0xff0000 #define I2C_MST_FIFO_STATUS_TX_SHIFT 16 +#define I2C_INTERFACE_TIMING_0 0x94 +#define I2C_THIGH_SHIFT 8 +#define I2C_INTERFACE_TIMING_1 0x98 + +#define I2C_STANDARD_MODE 100000 +#define I2C_FAST_MODE 400000 +#define I2C_FAST_PLUS_MODE 1000000 +#define I2C_HS_MODE 3500000 + +/* Packet header size in bytes */ +#define I2C_PACKET_HEADER_SIZE 12 + +/* + * Upto I2C_PIO_MODE_MAX_LEN bytes, controller will use PIO mode, + * above this, controller will use DMA to fill FIFO. + * MAX PIO len is 20 bytes excluding packet header. + */ +#define I2C_PIO_MODE_MAX_LEN 32 + /* * msg_end_type: The bus control which need to be send at end of transfer. * @MSG_END_STOP: Send stop pulse at end of transfer. @@ -142,7 +169,10 @@ enum msg_end_type { * @has_config_load_reg: Has the config load register to load the new * configuration. * @clk_divisor_hs_mode: Clock divisor in HS mode. - * @clk_divisor_std_fast_mode: Clock divisor in standard/fast mode. It is + * @clk_divisor_std_mode: Clock divisor in standard mode. It is + * applicable if there is no fast clock source i.e. single clock + * source. + * @clk_divisor_fast_mode: Clock divisor in fast mode. It is * applicable if there is no fast clock source i.e. single clock * source. * @clk_divisor_fast_plus_mode: Clock divisor in fast mode plus. It is @@ -157,6 +187,21 @@ enum msg_end_type { * be transferred in one go. * @quirks: i2c adapter quirks for limiting write/read transfer size and not * allowing 0 length transfers. + * @supports_bus_clear: Bus Clear support to recover from bus hang during + * SDA stuck low from device for some unknown reasons. + * @has_apb_dma: Support of APBDMA on corresponding Tegra chip. + * @tlow_std_mode: Low period of the clock in standard mode. + * @thigh_std_mode: High period of the clock in standard mode. + * @tlow_fast_fastplus_mode: Low period of the clock in fast/fast-plus modes. + * @thigh_fast_fastplus_mode: High period of the clock in fast/fast-plus modes. + * @setup_hold_time_std_mode: Setup and hold time for start and stop conditions + * in standard mode. + * @setup_hold_time_fast_fast_plus_mode: Setup and hold time for start and stop + * conditions in fast/fast-plus modes. + * @setup_hold_time_hs_mode: Setup and hold time for start and stop conditions + * in HS mode. + * @has_interface_timing_reg: Has interface timing register to program the tuned + * timing settings. */ struct tegra_i2c_hw_feature { bool has_continue_xfer_support; @@ -164,12 +209,23 @@ struct tegra_i2c_hw_feature { bool has_single_clk_source; bool has_config_load_reg; int clk_divisor_hs_mode; - int clk_divisor_std_fast_mode; + int clk_divisor_std_mode; + int clk_divisor_fast_mode; u16 clk_divisor_fast_plus_mode; bool has_multi_master_mode; bool has_slcg_override_reg; bool has_mst_fifo; const struct i2c_adapter_quirks *quirks; + bool supports_bus_clear; + bool has_apb_dma; + u8 tlow_std_mode; + u8 thigh_std_mode; + u8 tlow_fast_fastplus_mode; + u8 thigh_fast_fastplus_mode; + u32 setup_hold_time_std_mode; + u32 setup_hold_time_fast_fast_plus_mode; + u32 setup_hold_time_hs_mode; + bool has_interface_timing_reg; }; /** @@ -181,6 +237,7 @@ struct tegra_i2c_hw_feature { * @fast_clk: clock reference for fast clock of I2C controller * @rst: reset control for the I2C controller * @base: ioremapped registers cookie + * @base_phys: physical base address of the I2C controller * @cont_id: I2C controller ID, used for packet header * @irq: IRQ number of transfer complete interrupt * @irq_disabled: used to track whether or not the interrupt is enabled @@ -194,6 +251,13 @@ struct tegra_i2c_hw_feature { * @clk_divisor_non_hs_mode: clock divider for non-high-speed modes * @is_multimaster_mode: track if I2C controller is in multi-master mode * @xfer_lock: lock to serialize transfer submission and processing + * @tx_dma_chan: DMA transmit channel + * @rx_dma_chan: DMA receive channel + * @dma_phys: handle to DMA resources + * @dma_buf: pointer to allocated DMA buffer + * @dma_buf_size: DMA buffer size + * @is_curr_dma_xfer: indicates active DMA transfer + * @dma_complete: DMA completion notifier */ struct tegra_i2c_dev { struct device *dev; @@ -203,6 +267,7 @@ struct tegra_i2c_dev { struct clk *fast_clk; struct reset_control *rst; void __iomem *base; + phys_addr_t base_phys; int cont_id; int irq; bool irq_disabled; @@ -216,6 +281,13 @@ struct tegra_i2c_dev { u16 clk_divisor_non_hs_mode; bool is_multimaster_mode; spinlock_t xfer_lock; + struct dma_chan *tx_dma_chan; + struct dma_chan *rx_dma_chan; + dma_addr_t dma_phys; + u32 *dma_buf; + unsigned int dma_buf_size; + bool is_curr_dma_xfer; + struct completion dma_complete; }; static void dvc_writel(struct tegra_i2c_dev *i2c_dev, u32 val, @@ -284,6 +356,111 @@ static void tegra_i2c_unmask_irq(struct tegra_i2c_dev *i2c_dev, u32 mask) i2c_writel(i2c_dev, int_mask, I2C_INT_MASK); } +static void tegra_i2c_dma_complete(void *args) +{ + struct tegra_i2c_dev *i2c_dev = args; + + complete(&i2c_dev->dma_complete); +} + +static int tegra_i2c_dma_submit(struct tegra_i2c_dev *i2c_dev, size_t len) +{ + struct dma_async_tx_descriptor *dma_desc; + enum dma_transfer_direction dir; + struct dma_chan *chan; + + dev_dbg(i2c_dev->dev, "starting DMA for length: %zu\n", len); + reinit_completion(&i2c_dev->dma_complete); + dir = i2c_dev->msg_read ? DMA_DEV_TO_MEM : DMA_MEM_TO_DEV; + chan = i2c_dev->msg_read ? i2c_dev->rx_dma_chan : i2c_dev->tx_dma_chan; + dma_desc = dmaengine_prep_slave_single(chan, i2c_dev->dma_phys, + len, dir, DMA_PREP_INTERRUPT | + DMA_CTRL_ACK); + if (!dma_desc) { + dev_err(i2c_dev->dev, "failed to get DMA descriptor\n"); + return -EINVAL; + } + + dma_desc->callback = tegra_i2c_dma_complete; + dma_desc->callback_param = i2c_dev; + dmaengine_submit(dma_desc); + dma_async_issue_pending(chan); + return 0; +} + +static void tegra_i2c_release_dma(struct tegra_i2c_dev *i2c_dev) +{ + if (i2c_dev->dma_buf) { + dma_free_coherent(i2c_dev->dev, i2c_dev->dma_buf_size, + i2c_dev->dma_buf, i2c_dev->dma_phys); + i2c_dev->dma_buf = NULL; + } + + if (i2c_dev->tx_dma_chan) { + dma_release_channel(i2c_dev->tx_dma_chan); + i2c_dev->tx_dma_chan = NULL; + } + + if (i2c_dev->rx_dma_chan) { + dma_release_channel(i2c_dev->rx_dma_chan); + i2c_dev->rx_dma_chan = NULL; + } +} + +static int tegra_i2c_init_dma(struct tegra_i2c_dev *i2c_dev) +{ + struct dma_chan *chan; + u32 *dma_buf; + dma_addr_t dma_phys; + int err; + + if (!i2c_dev->hw->has_apb_dma) + return 0; + + if (!IS_ENABLED(CONFIG_TEGRA20_APB_DMA)) { + dev_dbg(i2c_dev->dev, "Support for APB DMA not enabled!\n"); + return 0; + } + + chan = dma_request_slave_channel_reason(i2c_dev->dev, "rx"); + if (IS_ERR(chan)) { + err = PTR_ERR(chan); + goto err_out; + } + + i2c_dev->rx_dma_chan = chan; + + chan = dma_request_slave_channel_reason(i2c_dev->dev, "tx"); + if (IS_ERR(chan)) { + err = PTR_ERR(chan); + goto err_out; + } + + i2c_dev->tx_dma_chan = chan; + + dma_buf = dma_alloc_coherent(i2c_dev->dev, i2c_dev->dma_buf_size, + &dma_phys, GFP_KERNEL | __GFP_NOWARN); + if (!dma_buf) { + dev_err(i2c_dev->dev, "failed to allocate the DMA buffer\n"); + err = -ENOMEM; + goto err_out; + } + + i2c_dev->dma_buf = dma_buf; + i2c_dev->dma_phys = dma_phys; + return 0; + +err_out: + tegra_i2c_release_dma(i2c_dev); + if (err != -EPROBE_DEFER) { + dev_err(i2c_dev->dev, "cannot use DMA: %d\n", err); + dev_err(i2c_dev->dev, "falling back to PIO\n"); + return 0; + } + + return err; +} + static int tegra_i2c_flush_fifos(struct tegra_i2c_dev *i2c_dev) { unsigned long timeout = jiffies + HZ; @@ -518,11 +695,13 @@ static int tegra_i2c_wait_for_config_load(struct tegra_i2c_dev *i2c_dev) return 0; } -static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev) +static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev, bool clk_reinit) { u32 val; int err; - u32 clk_divisor; + u32 clk_divisor, clk_multiplier; + u32 tsu_thd = 0; + u8 tlow, thigh; err = pm_runtime_get_sync(i2c_dev->dev); if (err < 0) { @@ -552,6 +731,41 @@ static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev) I2C_CLK_DIVISOR_STD_FAST_MODE_SHIFT; i2c_writel(i2c_dev, clk_divisor, I2C_CLK_DIVISOR); + if (i2c_dev->bus_clk_rate > I2C_STANDARD_MODE && + i2c_dev->bus_clk_rate <= I2C_FAST_PLUS_MODE) { + tlow = i2c_dev->hw->tlow_fast_fastplus_mode; + thigh = i2c_dev->hw->thigh_fast_fastplus_mode; + tsu_thd = i2c_dev->hw->setup_hold_time_fast_fast_plus_mode; + } else { + tlow = i2c_dev->hw->tlow_std_mode; + thigh = i2c_dev->hw->thigh_std_mode; + tsu_thd = i2c_dev->hw->setup_hold_time_std_mode; + } + + if (i2c_dev->hw->has_interface_timing_reg) { + val = (thigh << I2C_THIGH_SHIFT) | tlow; + i2c_writel(i2c_dev, val, I2C_INTERFACE_TIMING_0); + } + + /* + * configure setup and hold times only when tsu_thd is non-zero. + * otherwise, preserve the chip default values + */ + if (i2c_dev->hw->has_interface_timing_reg && tsu_thd) + i2c_writel(i2c_dev, tsu_thd, I2C_INTERFACE_TIMING_1); + + if (!clk_reinit) { + clk_multiplier = (tlow + thigh + 2); + clk_multiplier *= (i2c_dev->clk_divisor_non_hs_mode + 1); + err = clk_set_rate(i2c_dev->div_clk, + i2c_dev->bus_clk_rate * clk_multiplier); + if (err) { + dev_err(i2c_dev->dev, + "failed changing clock rate: %d\n", err); + goto err; + } + } + if (!i2c_dev->is_dvc) { u32 sl_cfg = i2c_readl(i2c_dev, I2C_SL_CNFG); @@ -561,16 +775,6 @@ static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev) i2c_writel(i2c_dev, 0x00, I2C_SL_ADDR2); } - if (i2c_dev->hw->has_mst_fifo) { - val = I2C_MST_FIFO_CONTROL_TX_TRIG(8) | - I2C_MST_FIFO_CONTROL_RX_TRIG(1); - i2c_writel(i2c_dev, val, I2C_MST_FIFO_CONTROL); - } else { - val = 7 << I2C_FIFO_CONTROL_TX_TRIG_SHIFT | - 0 << I2C_FIFO_CONTROL_RX_TRIG_SHIFT; - i2c_writel(i2c_dev, val, I2C_FIFO_CONTROL); - } - err = tegra_i2c_flush_fifos(i2c_dev); if (err) goto err; @@ -643,25 +847,44 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id) 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(); - } + /* + * I2C transfer is terminated during the bus clear so skip + * processing the other interrupts. + */ + if (i2c_dev->hw->supports_bus_clear && (status & I2C_INT_BUS_CLR_DONE)) + goto err; - 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 (!i2c_dev->is_curr_dma_xfer) { + 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); + } } i2c_writel(i2c_dev, status, I2C_INT_STATUS); if (i2c_dev->is_dvc) dvc_writel(i2c_dev, DVC_STATUS_I2C_DONE_INTR, DVC_STATUS); + /* + * During message read XFER_COMPLETE interrupt is triggered prior to + * DMA completion and during message write XFER_COMPLETE interrupt is + * triggered after DMA completion. + * PACKETS_XFER_COMPLETE indicates completion of all bytes of transfer. + * so forcing msg_buf_remaining to 0 in DMA mode. + */ if (status & I2C_INT_PACKET_XFER_COMPLETE) { + if (i2c_dev->is_curr_dma_xfer) + i2c_dev->msg_buf_remaining = 0; BUG_ON(i2c_dev->msg_buf_remaining); complete(&i2c_dev->msg_complete); } @@ -671,16 +894,135 @@ err: 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); + if (i2c_dev->hw->supports_bus_clear) + tegra_i2c_mask_irq(i2c_dev, I2C_INT_BUS_CLR_DONE); i2c_writel(i2c_dev, status, I2C_INT_STATUS); if (i2c_dev->is_dvc) dvc_writel(i2c_dev, DVC_STATUS_I2C_DONE_INTR, DVC_STATUS); + if (i2c_dev->is_curr_dma_xfer) { + if (i2c_dev->msg_read) + dmaengine_terminate_async(i2c_dev->rx_dma_chan); + else + dmaengine_terminate_async(i2c_dev->tx_dma_chan); + + complete(&i2c_dev->dma_complete); + } + complete(&i2c_dev->msg_complete); done: spin_unlock(&i2c_dev->xfer_lock); return IRQ_HANDLED; } +static void tegra_i2c_config_fifo_trig(struct tegra_i2c_dev *i2c_dev, + size_t len) +{ + u32 val, reg; + u8 dma_burst; + struct dma_slave_config slv_config = {0}; + struct dma_chan *chan; + int ret; + unsigned long reg_offset; + + if (i2c_dev->hw->has_mst_fifo) + reg = I2C_MST_FIFO_CONTROL; + else + reg = I2C_FIFO_CONTROL; + + if (i2c_dev->is_curr_dma_xfer) { + if (len & 0xF) + dma_burst = 1; + else if (len & 0x10) + dma_burst = 4; + else + dma_burst = 8; + + if (i2c_dev->msg_read) { + chan = i2c_dev->rx_dma_chan; + reg_offset = tegra_i2c_reg_addr(i2c_dev, I2C_RX_FIFO); + slv_config.src_addr = i2c_dev->base_phys + reg_offset; + slv_config.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; + slv_config.src_maxburst = dma_burst; + + if (i2c_dev->hw->has_mst_fifo) + val = I2C_MST_FIFO_CONTROL_RX_TRIG(dma_burst); + else + val = I2C_FIFO_CONTROL_RX_TRIG(dma_burst); + } else { + chan = i2c_dev->tx_dma_chan; + reg_offset = tegra_i2c_reg_addr(i2c_dev, I2C_TX_FIFO); + slv_config.dst_addr = i2c_dev->base_phys + reg_offset; + slv_config.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; + slv_config.dst_maxburst = dma_burst; + + if (i2c_dev->hw->has_mst_fifo) + val = I2C_MST_FIFO_CONTROL_TX_TRIG(dma_burst); + else + val = I2C_FIFO_CONTROL_TX_TRIG(dma_burst); + } + + slv_config.device_fc = true; + ret = dmaengine_slave_config(chan, &slv_config); + if (ret < 0) { + dev_err(i2c_dev->dev, "DMA slave config failed: %d\n", + ret); + dev_err(i2c_dev->dev, "falling back to PIO\n"); + tegra_i2c_release_dma(i2c_dev); + i2c_dev->is_curr_dma_xfer = false; + } else { + goto out; + } + } + + if (i2c_dev->hw->has_mst_fifo) + val = I2C_MST_FIFO_CONTROL_TX_TRIG(8) | + I2C_MST_FIFO_CONTROL_RX_TRIG(1); + else + val = I2C_FIFO_CONTROL_TX_TRIG(8) | + I2C_FIFO_CONTROL_RX_TRIG(1); +out: + i2c_writel(i2c_dev, val, reg); +} + +static int tegra_i2c_issue_bus_clear(struct i2c_adapter *adap) +{ + struct tegra_i2c_dev *i2c_dev = i2c_get_adapdata(adap); + int err; + unsigned long time_left; + u32 reg; + + reinit_completion(&i2c_dev->msg_complete); + reg = (I2C_BC_SCLK_THRESHOLD << I2C_BC_SCLK_THRESHOLD_SHIFT) | + I2C_BC_STOP_COND | I2C_BC_TERMINATE; + i2c_writel(i2c_dev, reg, I2C_BUS_CLEAR_CNFG); + if (i2c_dev->hw->has_config_load_reg) { + err = tegra_i2c_wait_for_config_load(i2c_dev); + if (err) + return err; + } + + reg |= I2C_BC_ENABLE; + i2c_writel(i2c_dev, reg, I2C_BUS_CLEAR_CNFG); + tegra_i2c_unmask_irq(i2c_dev, I2C_INT_BUS_CLR_DONE); + + time_left = wait_for_completion_timeout(&i2c_dev->msg_complete, + msecs_to_jiffies(50)); + if (time_left == 0) { + dev_err(i2c_dev->dev, "timed out for bus clear\n"); + return -ETIMEDOUT; + } + + reg = i2c_readl(i2c_dev, I2C_BUS_CLEAR_STATUS); + if (!(reg & I2C_BC_STATUS)) { + dev_err(i2c_dev->dev, + "un-recovered arbitration lost\n"); + return -EIO; + } + + return -EAGAIN; +} + static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev, struct i2c_msg *msg, enum msg_end_type end_state) { @@ -688,6 +1030,11 @@ static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev, u32 int_mask; unsigned long time_left; unsigned long flags; + size_t xfer_size; + u32 *buffer = NULL; + int err = 0; + bool dma; + u16 xfer_time = 100; tegra_i2c_flush_fifos(i2c_dev); @@ -697,19 +1044,63 @@ static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev, i2c_dev->msg_read = (msg->flags & I2C_M_RD); reinit_completion(&i2c_dev->msg_complete); + if (i2c_dev->msg_read) + xfer_size = msg->len; + else + xfer_size = msg->len + I2C_PACKET_HEADER_SIZE; + + xfer_size = ALIGN(xfer_size, BYTES_PER_FIFO_WORD); + i2c_dev->is_curr_dma_xfer = (xfer_size > I2C_PIO_MODE_MAX_LEN) && + i2c_dev->dma_buf; + tegra_i2c_config_fifo_trig(i2c_dev, xfer_size); + dma = i2c_dev->is_curr_dma_xfer; + /* + * Transfer time in mSec = Total bits / transfer rate + * Total bits = 9 bits per byte (including ACK bit) + Start & stop bits + */ + xfer_time += DIV_ROUND_CLOSEST(((xfer_size * 9) + 2) * MSEC_PER_SEC, + i2c_dev->bus_clk_rate); spin_lock_irqsave(&i2c_dev->xfer_lock, flags); int_mask = I2C_INT_NO_ACK | I2C_INT_ARBITRATION_LOST; tegra_i2c_unmask_irq(i2c_dev, int_mask); + if (dma) { + if (i2c_dev->msg_read) { + dma_sync_single_for_device(i2c_dev->dev, + i2c_dev->dma_phys, + xfer_size, + DMA_FROM_DEVICE); + err = tegra_i2c_dma_submit(i2c_dev, xfer_size); + if (err < 0) { + dev_err(i2c_dev->dev, + "starting RX DMA failed, err %d\n", + err); + goto unlock; + } + + } else { + dma_sync_single_for_cpu(i2c_dev->dev, + i2c_dev->dma_phys, + xfer_size, + DMA_TO_DEVICE); + buffer = i2c_dev->dma_buf; + } + } 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); + if (dma && !i2c_dev->msg_read) + *buffer++ = packet_header; + else + i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO); packet_header = msg->len - 1; - i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO); + if (dma && !i2c_dev->msg_read) + *buffer++ = packet_header; + else + i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO); packet_header = I2C_HEADER_IE_ENABLE; if (end_state == MSG_END_CONTINUE) @@ -726,31 +1117,85 @@ static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev, packet_header |= I2C_HEADER_CONT_ON_NAK; 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); + if (dma && !i2c_dev->msg_read) + *buffer++ = packet_header; + else + i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO); + + if (!i2c_dev->msg_read) { + if (dma) { + memcpy(buffer, msg->buf, msg->len); + dma_sync_single_for_device(i2c_dev->dev, + i2c_dev->dma_phys, + xfer_size, + DMA_TO_DEVICE); + err = tegra_i2c_dma_submit(i2c_dev, xfer_size); + if (err < 0) { + dev_err(i2c_dev->dev, + "starting TX DMA failed, err %d\n", + err); + goto unlock; + } + } else { + tegra_i2c_fill_tx_fifo(i2c_dev); + } + } 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) - int_mask |= I2C_INT_TX_FIFO_DATA_REQ; + if (!dma) { + 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); - spin_unlock_irqrestore(&i2c_dev->xfer_lock, flags); dev_dbg(i2c_dev->dev, "unmasked irq: %02x\n", i2c_readl(i2c_dev, I2C_INT_MASK)); +unlock: + spin_unlock_irqrestore(&i2c_dev->xfer_lock, flags); + + if (dma) { + if (err) + return err; + + time_left = wait_for_completion_timeout( + &i2c_dev->dma_complete, + msecs_to_jiffies(xfer_time)); + if (time_left == 0) { + dev_err(i2c_dev->dev, "DMA transfer timeout\n"); + dmaengine_terminate_sync(i2c_dev->msg_read ? + i2c_dev->rx_dma_chan : + i2c_dev->tx_dma_chan); + tegra_i2c_init(i2c_dev, true); + return -ETIMEDOUT; + } + + if (i2c_dev->msg_read && i2c_dev->msg_err == I2C_ERR_NONE) { + dma_sync_single_for_cpu(i2c_dev->dev, + i2c_dev->dma_phys, + xfer_size, + DMA_FROM_DEVICE); + memcpy(i2c_dev->msg_buf, i2c_dev->dma_buf, + msg->len); + } + + if (i2c_dev->msg_err != I2C_ERR_NONE) + dmaengine_synchronize(i2c_dev->msg_read ? + i2c_dev->rx_dma_chan : + i2c_dev->tx_dma_chan); + } + time_left = wait_for_completion_timeout(&i2c_dev->msg_complete, - TEGRA_I2C_TIMEOUT); + msecs_to_jiffies(xfer_time)); tegra_i2c_mask_irq(i2c_dev, int_mask); if (time_left == 0) { dev_err(i2c_dev->dev, "i2c transfer timed out\n"); - tegra_i2c_init(i2c_dev); + tegra_i2c_init(i2c_dev, true); return -ETIMEDOUT; } @@ -758,10 +1203,18 @@ static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev, time_left, completion_done(&i2c_dev->msg_complete), i2c_dev->msg_err); + i2c_dev->is_curr_dma_xfer = false; if (likely(i2c_dev->msg_err == I2C_ERR_NONE)) return 0; - tegra_i2c_init(i2c_dev); + tegra_i2c_init(i2c_dev, true); + /* start recovery upon arbitration loss in single master mode */ + if (i2c_dev->msg_err == I2C_ERR_ARBITRATION_LOST) { + if (!i2c_dev->is_multimaster_mode) + return i2c_recover_bus(&i2c_dev->adapter); + return -EAGAIN; + } + if (i2c_dev->msg_err == I2C_ERR_NO_ACK) { if (msg->flags & I2C_M_IGNORE_NAK) return 0; @@ -836,12 +1289,17 @@ static const struct i2c_algorithm tegra_i2c_algo = { /* payload size is only 12 bit */ static const struct i2c_adapter_quirks tegra_i2c_quirks = { .flags = I2C_AQ_NO_ZERO_LEN, - .max_read_len = 4096, - .max_write_len = 4096, + .max_read_len = SZ_4K, + .max_write_len = SZ_4K - I2C_PACKET_HEADER_SIZE, }; static const struct i2c_adapter_quirks tegra194_i2c_quirks = { .flags = I2C_AQ_NO_ZERO_LEN, + .max_write_len = SZ_64K - I2C_PACKET_HEADER_SIZE, +}; + +static struct i2c_bus_recovery_info tegra_i2c_recovery_info = { + .recover_bus = tegra_i2c_issue_bus_clear, }; static const struct tegra_i2c_hw_feature tegra20_i2c_hw = { @@ -849,13 +1307,24 @@ static const struct tegra_i2c_hw_feature tegra20_i2c_hw = { .has_per_pkt_xfer_complete_irq = false, .has_single_clk_source = false, .clk_divisor_hs_mode = 3, - .clk_divisor_std_fast_mode = 0, + .clk_divisor_std_mode = 0, + .clk_divisor_fast_mode = 0, .clk_divisor_fast_plus_mode = 0, .has_config_load_reg = false, .has_multi_master_mode = false, .has_slcg_override_reg = false, .has_mst_fifo = false, .quirks = &tegra_i2c_quirks, + .supports_bus_clear = false, + .has_apb_dma = true, + .tlow_std_mode = 0x4, + .thigh_std_mode = 0x2, + .tlow_fast_fastplus_mode = 0x4, + .thigh_fast_fastplus_mode = 0x2, + .setup_hold_time_std_mode = 0x0, + .setup_hold_time_fast_fast_plus_mode = 0x0, + .setup_hold_time_hs_mode = 0x0, + .has_interface_timing_reg = false, }; static const struct tegra_i2c_hw_feature tegra30_i2c_hw = { @@ -863,13 +1332,24 @@ static const struct tegra_i2c_hw_feature tegra30_i2c_hw = { .has_per_pkt_xfer_complete_irq = false, .has_single_clk_source = false, .clk_divisor_hs_mode = 3, - .clk_divisor_std_fast_mode = 0, + .clk_divisor_std_mode = 0, + .clk_divisor_fast_mode = 0, .clk_divisor_fast_plus_mode = 0, .has_config_load_reg = false, .has_multi_master_mode = false, .has_slcg_override_reg = false, .has_mst_fifo = false, .quirks = &tegra_i2c_quirks, + .supports_bus_clear = false, + .has_apb_dma = true, + .tlow_std_mode = 0x4, + .thigh_std_mode = 0x2, + .tlow_fast_fastplus_mode = 0x4, + .thigh_fast_fastplus_mode = 0x2, + .setup_hold_time_std_mode = 0x0, + .setup_hold_time_fast_fast_plus_mode = 0x0, + .setup_hold_time_hs_mode = 0x0, + .has_interface_timing_reg = false, }; static const struct tegra_i2c_hw_feature tegra114_i2c_hw = { @@ -877,13 +1357,24 @@ static const struct tegra_i2c_hw_feature tegra114_i2c_hw = { .has_per_pkt_xfer_complete_irq = true, .has_single_clk_source = true, .clk_divisor_hs_mode = 1, - .clk_divisor_std_fast_mode = 0x19, + .clk_divisor_std_mode = 0x19, + .clk_divisor_fast_mode = 0x19, .clk_divisor_fast_plus_mode = 0x10, .has_config_load_reg = false, .has_multi_master_mode = false, .has_slcg_override_reg = false, .has_mst_fifo = false, .quirks = &tegra_i2c_quirks, + .supports_bus_clear = true, + .has_apb_dma = true, + .tlow_std_mode = 0x4, + .thigh_std_mode = 0x2, + .tlow_fast_fastplus_mode = 0x4, + .thigh_fast_fastplus_mode = 0x2, + .setup_hold_time_std_mode = 0x0, + .setup_hold_time_fast_fast_plus_mode = 0x0, + .setup_hold_time_hs_mode = 0x0, + .has_interface_timing_reg = false, }; static const struct tegra_i2c_hw_feature tegra124_i2c_hw = { @@ -891,13 +1382,24 @@ static const struct tegra_i2c_hw_feature tegra124_i2c_hw = { .has_per_pkt_xfer_complete_irq = true, .has_single_clk_source = true, .clk_divisor_hs_mode = 1, - .clk_divisor_std_fast_mode = 0x19, + .clk_divisor_std_mode = 0x19, + .clk_divisor_fast_mode = 0x19, .clk_divisor_fast_plus_mode = 0x10, .has_config_load_reg = true, .has_multi_master_mode = false, .has_slcg_override_reg = true, .has_mst_fifo = false, .quirks = &tegra_i2c_quirks, + .supports_bus_clear = true, + .has_apb_dma = true, + .tlow_std_mode = 0x4, + .thigh_std_mode = 0x2, + .tlow_fast_fastplus_mode = 0x4, + .thigh_fast_fastplus_mode = 0x2, + .setup_hold_time_std_mode = 0x0, + .setup_hold_time_fast_fast_plus_mode = 0x0, + .setup_hold_time_hs_mode = 0x0, + .has_interface_timing_reg = true, }; static const struct tegra_i2c_hw_feature tegra210_i2c_hw = { @@ -905,32 +1407,80 @@ static const struct tegra_i2c_hw_feature tegra210_i2c_hw = { .has_per_pkt_xfer_complete_irq = true, .has_single_clk_source = true, .clk_divisor_hs_mode = 1, - .clk_divisor_std_fast_mode = 0x19, + .clk_divisor_std_mode = 0x19, + .clk_divisor_fast_mode = 0x19, .clk_divisor_fast_plus_mode = 0x10, .has_config_load_reg = true, - .has_multi_master_mode = true, + .has_multi_master_mode = false, .has_slcg_override_reg = true, .has_mst_fifo = false, .quirks = &tegra_i2c_quirks, + .supports_bus_clear = true, + .has_apb_dma = true, + .tlow_std_mode = 0x4, + .thigh_std_mode = 0x2, + .tlow_fast_fastplus_mode = 0x4, + .thigh_fast_fastplus_mode = 0x2, + .setup_hold_time_std_mode = 0, + .setup_hold_time_fast_fast_plus_mode = 0, + .setup_hold_time_hs_mode = 0, + .has_interface_timing_reg = true, }; -static const struct tegra_i2c_hw_feature tegra194_i2c_hw = { +static const struct tegra_i2c_hw_feature tegra186_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, + .clk_divisor_std_mode = 0x16, + .clk_divisor_fast_mode = 0x19, .clk_divisor_fast_plus_mode = 0x10, .has_config_load_reg = true, + .has_multi_master_mode = false, + .has_slcg_override_reg = true, + .has_mst_fifo = false, + .quirks = &tegra_i2c_quirks, + .supports_bus_clear = true, + .has_apb_dma = false, + .tlow_std_mode = 0x4, + .thigh_std_mode = 0x3, + .tlow_fast_fastplus_mode = 0x4, + .thigh_fast_fastplus_mode = 0x2, + .setup_hold_time_std_mode = 0, + .setup_hold_time_fast_fast_plus_mode = 0, + .setup_hold_time_hs_mode = 0, + .has_interface_timing_reg = true, +}; + +static const struct tegra_i2c_hw_feature tegra194_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_mode = 0x4f, + .clk_divisor_fast_mode = 0x3c, + .clk_divisor_fast_plus_mode = 0x16, + .has_config_load_reg = true, .has_multi_master_mode = true, .has_slcg_override_reg = true, .has_mst_fifo = true, .quirks = &tegra194_i2c_quirks, + .supports_bus_clear = true, + .has_apb_dma = false, + .tlow_std_mode = 0x8, + .thigh_std_mode = 0x7, + .tlow_fast_fastplus_mode = 0x2, + .thigh_fast_fastplus_mode = 0x2, + .setup_hold_time_std_mode = 0x08080808, + .setup_hold_time_fast_fast_plus_mode = 0x02020202, + .setup_hold_time_hs_mode = 0x090909, + .has_interface_timing_reg = true, }; /* Match table for of_platform binding */ static const struct of_device_id tegra_i2c_of_match[] = { { .compatible = "nvidia,tegra194-i2c", .data = &tegra194_i2c_hw, }, + { .compatible = "nvidia,tegra186-i2c", .data = &tegra186_i2c_hw, }, { .compatible = "nvidia,tegra210-i2c", .data = &tegra210_i2c_hw, }, { .compatible = "nvidia,tegra124-i2c", .data = &tegra124_i2c_hw, }, { .compatible = "nvidia,tegra114-i2c", .data = &tegra114_i2c_hw, }, @@ -948,11 +1498,12 @@ static int tegra_i2c_probe(struct platform_device *pdev) struct clk *div_clk; struct clk *fast_clk; void __iomem *base; + phys_addr_t base_phys; int irq; int ret = 0; - int clk_multiplier = I2C_CLK_MULTIPLIER_STD_FAST_MODE; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + base_phys = res->start; base = devm_ioremap_resource(&pdev->dev, res); if (IS_ERR(base)) return PTR_ERR(base); @@ -975,8 +1526,11 @@ static int tegra_i2c_probe(struct platform_device *pdev) return -ENOMEM; i2c_dev->base = base; + i2c_dev->base_phys = base_phys; i2c_dev->div_clk = div_clk; i2c_dev->adapter.algo = &tegra_i2c_algo; + i2c_dev->adapter.retries = 1; + i2c_dev->adapter.timeout = 6 * HZ; i2c_dev->irq = irq; i2c_dev->cont_id = pdev->id; i2c_dev->dev = &pdev->dev; @@ -993,7 +1547,10 @@ static int tegra_i2c_probe(struct platform_device *pdev) i2c_dev->is_dvc = of_device_is_compatible(pdev->dev.of_node, "nvidia,tegra20-i2c-dvc"); i2c_dev->adapter.quirks = i2c_dev->hw->quirks; + i2c_dev->dma_buf_size = i2c_dev->adapter.quirks->max_write_len + + I2C_PACKET_HEADER_SIZE; init_completion(&i2c_dev->msg_complete); + init_completion(&i2c_dev->dma_complete); spin_lock_init(&i2c_dev->xfer_lock); if (!i2c_dev->hw->has_single_clk_source) { @@ -1015,20 +1572,17 @@ static int tegra_i2c_probe(struct platform_device *pdev) } } - i2c_dev->clk_divisor_non_hs_mode = - i2c_dev->hw->clk_divisor_std_fast_mode; - if (i2c_dev->hw->clk_divisor_fast_plus_mode && - (i2c_dev->bus_clk_rate == 1000000)) + if (i2c_dev->bus_clk_rate > I2C_FAST_MODE && + i2c_dev->bus_clk_rate <= I2C_FAST_PLUS_MODE) i2c_dev->clk_divisor_non_hs_mode = - i2c_dev->hw->clk_divisor_fast_plus_mode; - - clk_multiplier *= (i2c_dev->clk_divisor_non_hs_mode + 1); - ret = clk_set_rate(i2c_dev->div_clk, - i2c_dev->bus_clk_rate * clk_multiplier); - if (ret) { - dev_err(i2c_dev->dev, "Clock rate change failed %d\n", ret); - goto unprepare_fast_clk; - } + i2c_dev->hw->clk_divisor_fast_plus_mode; + else if (i2c_dev->bus_clk_rate > I2C_STANDARD_MODE && + i2c_dev->bus_clk_rate <= I2C_FAST_MODE) + i2c_dev->clk_divisor_non_hs_mode = + i2c_dev->hw->clk_divisor_fast_mode; + else + i2c_dev->clk_divisor_non_hs_mode = + i2c_dev->hw->clk_divisor_std_mode; ret = clk_prepare(i2c_dev->div_clk); if (ret < 0) { @@ -1054,17 +1608,24 @@ static int tegra_i2c_probe(struct platform_device *pdev) } } - ret = tegra_i2c_init(i2c_dev); + if (i2c_dev->hw->supports_bus_clear) + i2c_dev->adapter.bus_recovery_info = &tegra_i2c_recovery_info; + + ret = tegra_i2c_init_dma(i2c_dev); + if (ret < 0) + goto disable_div_clk; + + ret = tegra_i2c_init(i2c_dev, false); if (ret) { dev_err(&pdev->dev, "Failed to initialize i2c controller\n"); - goto disable_div_clk; + goto release_dma; } ret = devm_request_irq(&pdev->dev, i2c_dev->irq, tegra_i2c_isr, 0, dev_name(&pdev->dev), i2c_dev); if (ret) { dev_err(&pdev->dev, "Failed to request irq %i\n", i2c_dev->irq); - goto disable_div_clk; + goto release_dma; } i2c_set_adapdata(&i2c_dev->adapter, i2c_dev); @@ -1078,10 +1639,13 @@ static int tegra_i2c_probe(struct platform_device *pdev) ret = i2c_add_numbered_adapter(&i2c_dev->adapter); if (ret) - goto disable_div_clk; + goto release_dma; return 0; +release_dma: + tegra_i2c_release_dma(i2c_dev); + disable_div_clk: if (i2c_dev->is_multimaster_mode) clk_disable(i2c_dev->div_clk); @@ -1118,6 +1682,7 @@ static int tegra_i2c_remove(struct platform_device *pdev) if (!i2c_dev->hw->has_single_clk_source) clk_unprepare(i2c_dev->fast_clk); + tegra_i2c_release_dma(i2c_dev); return 0; } @@ -1141,18 +1706,7 @@ static struct platform_driver tegra_i2c_driver = { }, }; -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_platform_driver(tegra_i2c_driver); MODULE_DESCRIPTION("nVidia Tegra2 I2C Bus Controller driver"); MODULE_AUTHOR("Colin Cross"); |