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path: root/drivers/spi/spi-rzv2m-csi.c
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Diffstat (limited to 'drivers/spi/spi-rzv2m-csi.c')
-rw-r--r--drivers/spi/spi-rzv2m-csi.c127
1 files changed, 83 insertions, 44 deletions
diff --git a/drivers/spi/spi-rzv2m-csi.c b/drivers/spi/spi-rzv2m-csi.c
index d0f51b17aa..741e0f44c4 100644
--- a/drivers/spi/spi-rzv2m-csi.c
+++ b/drivers/spi/spi-rzv2m-csi.c
@@ -11,6 +11,7 @@
#include <linux/interrupt.h>
#include <linux/iopoll.h>
#include <linux/log2.h>
+#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/property.h>
#include <linux/reset.h>
@@ -38,6 +39,9 @@
#define CSI_MODE_SETUP 0x00000040
/* CSI_CLKSEL */
+#define CSI_CLKSEL_SS_ENA BIT(19)
+#define CSI_CLKSEL_SS_POL BIT(18)
+#define CSI_CLKSEL_SS (CSI_CLKSEL_SS_ENA | CSI_CLKSEL_SS_POL)
#define CSI_CLKSEL_CKP BIT(17)
#define CSI_CLKSEL_DAP BIT(16)
#define CSI_CLKSEL_MODE (CSI_CLKSEL_CKP|CSI_CLKSEL_DAP)
@@ -82,6 +86,10 @@
#define CSI_MAX_SPI_SCKO (8 * HZ_PER_MHZ)
+#define CSI_CLKSEL_SS_DISABLED 0
+#define CSI_CLKSEL_SS_ENABLED_ACTIVE_LOW BIT(1)
+#define CSI_CLKSEL_SS_ENABLED_ACTIVE_HIGH GENMASK(1, 0)
+
struct rzv2m_csi_priv {
void __iomem *base;
struct clk *csiclk;
@@ -99,6 +107,8 @@ struct rzv2m_csi_priv {
wait_queue_head_t wait;
u32 errors;
u32 status;
+ bool target_aborted;
+ bool use_ss_pin;
};
static void rzv2m_csi_reg_write_bit(const struct rzv2m_csi_priv *csi,
@@ -193,6 +203,14 @@ static int rzv2m_csi_read_rxfifo(struct rzv2m_csi_priv *csi)
return 0;
}
+static inline void rzv2m_csi_empty_rxfifo(struct rzv2m_csi_priv *csi)
+{
+ unsigned int i;
+
+ for (i = 0; i < csi->words_to_transfer; i++)
+ readl(csi->base + CSI_IFIFO);
+}
+
static inline void rzv2m_csi_calc_current_transfer(struct rzv2m_csi_priv *csi)
{
unsigned int bytes_transferred = max(csi->bytes_received, csi->bytes_sent);
@@ -279,32 +297,23 @@ static int rzv2m_csi_wait_for_interrupt(struct rzv2m_csi_priv *csi,
rzv2m_csi_enable_irqs(csi, enable_bits);
- ret = wait_event_timeout(csi->wait,
- ((csi->status & wait_mask) == wait_mask) ||
- csi->errors, HZ);
+ if (spi_controller_is_target(csi->controller)) {
+ ret = wait_event_interruptible(csi->wait,
+ ((csi->status & wait_mask) == wait_mask) ||
+ csi->errors || csi->target_aborted);
+ if (ret || csi->target_aborted)
+ ret = -EINTR;
+ } else {
+ ret = wait_event_timeout(csi->wait,
+ ((csi->status & wait_mask) == wait_mask) ||
+ csi->errors, HZ) == 0 ? -ETIMEDOUT : 0;
+ }
rzv2m_csi_disable_irqs(csi, enable_bits);
if (csi->errors)
return -EIO;
- if (!ret)
- return -ETIMEDOUT;
-
- return 0;
-}
-
-static int rzv2m_csi_wait_for_tx_empty(struct rzv2m_csi_priv *csi)
-{
- int ret;
-
- if (readl(csi->base + CSI_OFIFOL) == 0)
- return 0;
-
- ret = rzv2m_csi_wait_for_interrupt(csi, CSI_INT_TREND, CSI_CNT_TREND_E);
- if (ret == -ETIMEDOUT)
- csi->errors |= TX_TIMEOUT_ERROR;
-
return ret;
}
@@ -312,7 +321,7 @@ static inline int rzv2m_csi_wait_for_rx_ready(struct rzv2m_csi_priv *csi)
{
int ret;
- if (readl(csi->base + CSI_IFIFOL) == csi->bytes_to_transfer)
+ if (readl(csi->base + CSI_IFIFOL) >= csi->bytes_to_transfer)
return 0;
ret = rzv2m_csi_wait_for_interrupt(csi, CSI_INT_R_TRGR,
@@ -388,6 +397,7 @@ static void rzv2m_csi_setup_operating_mode(struct rzv2m_csi_priv *csi,
static int rzv2m_csi_setup(struct spi_device *spi)
{
struct rzv2m_csi_priv *csi = spi_controller_get_devdata(spi->controller);
+ u32 slave_selection = CSI_CLKSEL_SS_DISABLED;
int ret;
rzv2m_csi_sw_reset(csi, 0);
@@ -402,8 +412,17 @@ static int rzv2m_csi_setup(struct spi_device *spi)
rzv2m_csi_reg_write_bit(csi, CSI_MODE, CSI_MODE_DIR,
!!(spi->mode & SPI_LSB_FIRST));
- /* Set the operation mode as master */
- rzv2m_csi_reg_write_bit(csi, CSI_CLKSEL, CSI_CLKSEL_SLAVE, 0);
+ /* Set the role, 1 for target and 0 for host */
+ rzv2m_csi_reg_write_bit(csi, CSI_CLKSEL, CSI_CLKSEL_SLAVE,
+ !!spi_controller_is_target(csi->controller));
+
+ if (csi->use_ss_pin)
+ slave_selection = spi->mode & SPI_CS_HIGH ?
+ CSI_CLKSEL_SS_ENABLED_ACTIVE_HIGH :
+ CSI_CLKSEL_SS_ENABLED_ACTIVE_LOW;
+
+ /* Configure the slave selection (SS) pin */
+ rzv2m_csi_reg_write_bit(csi, CSI_CLKSEL, CSI_CLKSEL_SS, slave_selection);
/* Give the IP a SW reset */
ret = rzv2m_csi_sw_reset(csi, 1);
@@ -431,9 +450,13 @@ static int rzv2m_csi_pio_transfer(struct rzv2m_csi_priv *csi)
/* Make sure the TX FIFO is empty */
writel(0, csi->base + CSI_OFIFOL);
+ /* Make sure the RX FIFO is empty */
+ writel(0, csi->base + CSI_IFIFOL);
+
csi->bytes_sent = 0;
csi->bytes_received = 0;
csi->errors = 0;
+ csi->target_aborted = false;
rzv2m_csi_disable_all_irqs(csi);
rzv2m_csi_clear_all_irqs(csi);
@@ -452,28 +475,21 @@ static int rzv2m_csi_pio_transfer(struct rzv2m_csi_priv *csi)
rzv2m_csi_enable_irqs(csi, CSI_INT_OVERF | CSI_INT_UNDER);
- /* Make sure the RX FIFO is empty */
- writel(0, csi->base + CSI_IFIFOL);
-
writel(readl(csi->base + CSI_INT), csi->base + CSI_INT);
csi->status = 0;
- rzv2m_csi_start_stop_operation(csi, 1, false);
-
/* TX */
if (csi->txbuf) {
ret = rzv2m_csi_fill_txfifo(csi);
if (ret)
break;
- ret = rzv2m_csi_wait_for_tx_empty(csi);
- if (ret)
- break;
-
if (csi->bytes_sent == csi->buffer_len)
tx_completed = true;
}
+ rzv2m_csi_start_stop_operation(csi, 1, false);
+
/*
* Make sure the RX FIFO contains the desired number of words.
* We then either flush its content, or we copy it onto
@@ -483,31 +499,28 @@ static int rzv2m_csi_pio_transfer(struct rzv2m_csi_priv *csi)
if (ret)
break;
- /* RX */
- if (csi->rxbuf) {
+ if (!spi_controller_is_target(csi->controller))
rzv2m_csi_start_stop_operation(csi, 0, false);
+ /* RX */
+ if (csi->rxbuf) {
ret = rzv2m_csi_read_rxfifo(csi);
if (ret)
break;
if (csi->bytes_received == csi->buffer_len)
rx_completed = true;
+ } else {
+ rzv2m_csi_empty_rxfifo(csi);
}
- ret = rzv2m_csi_start_stop_operation(csi, 0, true);
- if (ret)
- goto pio_quit;
-
if (csi->errors) {
ret = -EIO;
- goto pio_quit;
+ break;
}
}
rzv2m_csi_start_stop_operation(csi, 0, true);
-
-pio_quit:
rzv2m_csi_disable_all_irqs(csi);
rzv2m_csi_enable_rx_trigger(csi, false);
rzv2m_csi_clear_all_irqs(csi);
@@ -529,7 +542,8 @@ static int rzv2m_csi_transfer_one(struct spi_controller *controller,
rzv2m_csi_setup_operating_mode(csi, transfer);
- rzv2m_csi_setup_clock(csi, transfer->speed_hz);
+ if (!spi_controller_is_target(csi->controller))
+ rzv2m_csi_setup_clock(csi, transfer->speed_hz);
ret = rzv2m_csi_pio_transfer(csi);
if (ret) {
@@ -546,24 +560,48 @@ static int rzv2m_csi_transfer_one(struct spi_controller *controller,
return ret;
}
+static int rzv2m_csi_target_abort(struct spi_controller *ctlr)
+{
+ struct rzv2m_csi_priv *csi = spi_controller_get_devdata(ctlr);
+
+ csi->target_aborted = true;
+ wake_up(&csi->wait);
+
+ return 0;
+}
+
static int rzv2m_csi_probe(struct platform_device *pdev)
{
+ struct device_node *np = pdev->dev.of_node;
struct spi_controller *controller;
struct device *dev = &pdev->dev;
struct rzv2m_csi_priv *csi;
struct reset_control *rstc;
+ bool target_mode;
int irq;
int ret;
- controller = devm_spi_alloc_host(dev, sizeof(*csi));
+ target_mode = of_property_read_bool(np, "spi-slave");
+
+ if (target_mode)
+ controller = devm_spi_alloc_target(dev, sizeof(*csi));
+ else
+ controller = devm_spi_alloc_host(dev, sizeof(*csi));
+
if (!controller)
return -ENOMEM;
csi = spi_controller_get_devdata(controller);
platform_set_drvdata(pdev, csi);
+ csi->use_ss_pin = false;
+ if (spi_controller_is_target(controller) &&
+ !of_property_read_bool(np, "renesas,csi-no-ss"))
+ csi->use_ss_pin = true;
+
csi->dev = dev;
csi->controller = controller;
+ csi->target_aborted = false;
csi->base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(csi->base))
@@ -589,11 +627,12 @@ static int rzv2m_csi_probe(struct platform_device *pdev)
init_waitqueue_head(&csi->wait);
- controller->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST;
+ controller->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST | SPI_CS_HIGH;
controller->bits_per_word_mask = SPI_BPW_MASK(16) | SPI_BPW_MASK(8);
controller->setup = rzv2m_csi_setup;
controller->transfer_one = rzv2m_csi_transfer_one;
controller->use_gpio_descriptors = true;
+ controller->target_abort = rzv2m_csi_target_abort;
device_set_node(&controller->dev, dev_fwnode(dev));
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-12 10:28:22 +0000