summaryrefslogtreecommitdiffstats
path: root/drivers/spi/spi-tegra114.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/spi/spi-tegra114.c')
-rw-r--r--drivers/spi/spi-tegra114.c170
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);