diff options
Diffstat (limited to 'drivers/spi/spi-tegra114.c')
| -rw-r--r-- | drivers/spi/spi-tegra114.c | 170 |
1 files changed, 154 insertions, 16 deletions
diff --git a/drivers/spi/spi-tegra114.c b/drivers/spi/spi-tegra114.c index d22f4d10413f..39374c2edcf3 100644 --- a/drivers/spi/spi-tegra114.c +++ b/drivers/spi/spi-tegra114.c @@ -84,8 +84,10 @@ (reg = (((val) & 0x1) << ((cs) * 8 + 5)) | \ ((reg) & ~(1 << ((cs) * 8 + 5)))) #define SPI_SET_CYCLES_BETWEEN_PACKETS(reg, cs, val) \ - (reg = (((val) & 0xF) << ((cs) * 8)) | \ - ((reg) & ~(0xF << ((cs) * 8)))) + (reg = (((val) & 0x1F) << ((cs) * 8)) | \ + ((reg) & ~(0x1F << ((cs) * 8)))) +#define MAX_SETUP_HOLD_CYCLES 16 +#define MAX_INACTIVE_CYCLES 32 #define SPI_TRANS_STATUS 0x010 #define SPI_BLK_CNT(val) (((val) >> 0) & 0xFFFF) @@ -156,6 +158,11 @@ struct tegra_spi_soc_data { bool has_intr_mask_reg; }; +struct tegra_spi_client_data { + int tx_clk_tap_delay; + int rx_clk_tap_delay; +}; + struct tegra_spi_data { struct device *dev; struct spi_master *master; @@ -182,6 +189,7 @@ struct tegra_spi_data { unsigned dma_buf_size; unsigned max_buf_size; bool is_curr_dma_xfer; + bool use_hw_based_cs; struct completion rx_dma_complete; struct completion tx_dma_complete; @@ -194,6 +202,10 @@ struct tegra_spi_data { u32 command1_reg; u32 dma_control_reg; u32 def_command1_reg; + u32 def_command2_reg; + u32 spi_cs_timing1; + u32 spi_cs_timing2; + u8 last_used_cs; struct completion xfer_completion; struct spi_transfer *curr_xfer; @@ -711,14 +723,55 @@ static void tegra_spi_deinit_dma_param(struct tegra_spi_data *tspi, dma_release_channel(dma_chan); } +static void tegra_spi_set_hw_cs_timing(struct spi_device *spi, u8 setup_dly, + u8 hold_dly, u8 inactive_dly) +{ + struct tegra_spi_data *tspi = spi_master_get_devdata(spi->master); + u32 setup_hold; + u32 spi_cs_timing; + u32 inactive_cycles; + u8 cs_state; + + setup_dly = min_t(u8, setup_dly, MAX_SETUP_HOLD_CYCLES); + hold_dly = min_t(u8, hold_dly, MAX_SETUP_HOLD_CYCLES); + if (setup_dly && hold_dly) { + setup_hold = SPI_SETUP_HOLD(setup_dly - 1, hold_dly - 1); + spi_cs_timing = SPI_CS_SETUP_HOLD(tspi->spi_cs_timing1, + spi->chip_select, + setup_hold); + if (tspi->spi_cs_timing1 != spi_cs_timing) { + tspi->spi_cs_timing1 = spi_cs_timing; + tegra_spi_writel(tspi, spi_cs_timing, SPI_CS_TIMING1); + } + } + + inactive_cycles = min_t(u8, inactive_dly, MAX_INACTIVE_CYCLES); + if (inactive_cycles) + inactive_cycles--; + cs_state = inactive_cycles ? 0 : 1; + spi_cs_timing = tspi->spi_cs_timing2; + SPI_SET_CS_ACTIVE_BETWEEN_PACKETS(spi_cs_timing, spi->chip_select, + cs_state); + SPI_SET_CYCLES_BETWEEN_PACKETS(spi_cs_timing, spi->chip_select, + inactive_cycles); + if (tspi->spi_cs_timing2 != spi_cs_timing) { + tspi->spi_cs_timing2 = spi_cs_timing; + tegra_spi_writel(tspi, spi_cs_timing, SPI_CS_TIMING2); + } +} + static u32 tegra_spi_setup_transfer_one(struct spi_device *spi, - struct spi_transfer *t, bool is_first_of_msg) + struct spi_transfer *t, + bool is_first_of_msg, + bool is_single_xfer) { struct tegra_spi_data *tspi = spi_master_get_devdata(spi->master); + struct tegra_spi_client_data *cdata = spi->controller_data; u32 speed = t->speed_hz; u8 bits_per_word = t->bits_per_word; - u32 command1; + u32 command1, command2; int req_mode; + u32 tx_tap = 0, rx_tap = 0; if (speed != tspi->cur_speed) { clk_set_rate(tspi->clk, speed); @@ -765,13 +818,34 @@ static u32 tegra_spi_setup_transfer_one(struct spi_device *spi, } else tegra_spi_writel(tspi, command1, SPI_COMMAND1); - command1 |= SPI_CS_SW_HW; - if (spi->mode & SPI_CS_HIGH) - command1 |= SPI_CS_SW_VAL; - else - command1 &= ~SPI_CS_SW_VAL; + /* GPIO based chip select control */ + if (spi->cs_gpiod) + gpiod_set_value(spi->cs_gpiod, 1); + + if (is_single_xfer && !(t->cs_change)) { + tspi->use_hw_based_cs = true; + command1 &= ~(SPI_CS_SW_HW | SPI_CS_SW_VAL); + } else { + tspi->use_hw_based_cs = false; + command1 |= SPI_CS_SW_HW; + if (spi->mode & SPI_CS_HIGH) + command1 |= SPI_CS_SW_VAL; + else + command1 &= ~SPI_CS_SW_VAL; + } + + if (tspi->last_used_cs != spi->chip_select) { + if (cdata && cdata->tx_clk_tap_delay) + tx_tap = cdata->tx_clk_tap_delay; + if (cdata && cdata->rx_clk_tap_delay) + rx_tap = cdata->rx_clk_tap_delay; + command2 = SPI_TX_TAP_DELAY(tx_tap) | + SPI_RX_TAP_DELAY(rx_tap); + if (command2 != tspi->def_command2_reg) + tegra_spi_writel(tspi, command2, SPI_COMMAND2); + tspi->last_used_cs = spi->chip_select; + } - tegra_spi_writel(tspi, 0, SPI_COMMAND2); } else { command1 = tspi->command1_reg; command1 &= ~SPI_BIT_LENGTH(~0); @@ -827,9 +901,42 @@ static int tegra_spi_start_transfer_one(struct spi_device *spi, return ret; } +static struct tegra_spi_client_data + *tegra_spi_parse_cdata_dt(struct spi_device *spi) +{ + struct tegra_spi_client_data *cdata; + struct device_node *slave_np; + + slave_np = spi->dev.of_node; + if (!slave_np) { + dev_dbg(&spi->dev, "device node not found\n"); + return NULL; + } + + cdata = kzalloc(sizeof(*cdata), GFP_KERNEL); + if (!cdata) + return NULL; + + of_property_read_u32(slave_np, "nvidia,tx-clk-tap-delay", + &cdata->tx_clk_tap_delay); + of_property_read_u32(slave_np, "nvidia,rx-clk-tap-delay", + &cdata->rx_clk_tap_delay); + return cdata; +} + +static void tegra_spi_cleanup(struct spi_device *spi) +{ + struct tegra_spi_client_data *cdata = spi->controller_data; + + spi->controller_data = NULL; + if (spi->dev.of_node) + kfree(cdata); +} + static int tegra_spi_setup(struct spi_device *spi) { struct tegra_spi_data *tspi = spi_master_get_devdata(spi->master); + struct tegra_spi_client_data *cdata = spi->controller_data; u32 val; unsigned long flags; int ret; @@ -840,9 +947,16 @@ static int tegra_spi_setup(struct spi_device *spi) spi->mode & SPI_CPHA ? "" : "~", spi->max_speed_hz); + if (!cdata) { + cdata = tegra_spi_parse_cdata_dt(spi); + spi->controller_data = cdata; + } + ret = pm_runtime_get_sync(tspi->dev); if (ret < 0) { dev_err(tspi->dev, "pm runtime failed, e = %d\n", ret); + if (cdata) + tegra_spi_cleanup(spi); return ret; } @@ -853,6 +967,10 @@ static int tegra_spi_setup(struct spi_device *spi) } spin_lock_irqsave(&tspi->lock, flags); + /* GPIO based chip select control */ + if (spi->cs_gpiod) + gpiod_set_value(spi->cs_gpiod, 0); + val = tspi->def_command1_reg; if (spi->mode & SPI_CS_HIGH) val &= ~SPI_CS_POL_INACTIVE(spi->chip_select); @@ -882,11 +1000,18 @@ static void tegra_spi_transfer_end(struct spi_device *spi) struct tegra_spi_data *tspi = spi_master_get_devdata(spi->master); int cs_val = (spi->mode & SPI_CS_HIGH) ? 0 : 1; - if (cs_val) - tspi->command1_reg |= SPI_CS_SW_VAL; - else - tspi->command1_reg &= ~SPI_CS_SW_VAL; - tegra_spi_writel(tspi, tspi->command1_reg, SPI_COMMAND1); + /* GPIO based chip select control */ + if (spi->cs_gpiod) + gpiod_set_value(spi->cs_gpiod, 0); + + if (!tspi->use_hw_based_cs) { + if (cs_val) + tspi->command1_reg |= SPI_CS_SW_VAL; + else + tspi->command1_reg &= ~SPI_CS_SW_VAL; + tegra_spi_writel(tspi, tspi->command1_reg, SPI_COMMAND1); + } + tegra_spi_writel(tspi, tspi->def_command1_reg, SPI_COMMAND1); } @@ -913,16 +1038,19 @@ static int tegra_spi_transfer_one_message(struct spi_master *master, struct spi_device *spi = msg->spi; int ret; bool skip = false; + int single_xfer; msg->status = 0; msg->actual_length = 0; + single_xfer = list_is_singular(&msg->transfers); list_for_each_entry(xfer, &msg->transfers, transfer_list) { u32 cmd1; reinit_completion(&tspi->xfer_completion); - cmd1 = tegra_spi_setup_transfer_one(spi, xfer, is_first_msg); + cmd1 = tegra_spi_setup_transfer_one(spi, xfer, is_first_msg, + single_xfer); if (!xfer->len) { ret = 0; @@ -955,6 +1083,7 @@ static int tegra_spi_transfer_one_message(struct spi_master *master, reset_control_assert(tspi->rst); udelay(2); reset_control_deassert(tspi->rst); + tspi->last_used_cs = master->num_chipselect + 1; goto complete_xfer; } @@ -1188,11 +1317,14 @@ static int tegra_spi_probe(struct platform_device *pdev) master->max_speed_hz = 25000000; /* 25MHz */ /* the spi->mode bits understood by this driver: */ + master->use_gpio_descriptors = true; master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST | SPI_TX_DUAL | SPI_RX_DUAL | SPI_3WIRE; master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32); master->setup = tegra_spi_setup; + master->cleanup = tegra_spi_cleanup; master->transfer_one_message = tegra_spi_transfer_one_message; + master->set_cs_timing = tegra_spi_set_hw_cs_timing; master->num_chipselect = MAX_CHIP_SELECT; master->auto_runtime_pm = true; bus_num = of_alias_get_id(pdev->dev.of_node, "spi"); @@ -1268,6 +1400,10 @@ static int tegra_spi_probe(struct platform_device *pdev) reset_control_deassert(tspi->rst); tspi->def_command1_reg = SPI_M_S; tegra_spi_writel(tspi, tspi->def_command1_reg, SPI_COMMAND1); + tspi->spi_cs_timing1 = tegra_spi_readl(tspi, SPI_CS_TIMING1); + tspi->spi_cs_timing2 = tegra_spi_readl(tspi, SPI_CS_TIMING2); + tspi->def_command2_reg = tegra_spi_readl(tspi, SPI_COMMAND2); + tspi->last_used_cs = master->num_chipselect + 1; pm_runtime_put(&pdev->dev); ret = request_threaded_irq(tspi->irq, tegra_spi_isr, tegra_spi_isr_thread, IRQF_ONESHOT, @@ -1340,6 +1476,8 @@ static int tegra_spi_resume(struct device *dev) return ret; } tegra_spi_writel(tspi, tspi->command1_reg, SPI_COMMAND1); + tegra_spi_writel(tspi, tspi->def_command2_reg, SPI_COMMAND2); + tspi->last_used_cs = master->num_chipselect + 1; pm_runtime_put(dev); return spi_master_resume(master); |