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path: root/drivers/spi/spi-rspi.c
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Diffstat (limited to 'drivers/spi/spi-rspi.c')
-rw-r--r--drivers/spi/spi-rspi.c81
1 files changed, 52 insertions, 29 deletions
diff --git a/drivers/spi/spi-rspi.c b/drivers/spi/spi-rspi.c
index cbc2387d450c..e39fd38f5180 100644
--- a/drivers/spi/spi-rspi.c
+++ b/drivers/spi/spi-rspi.c
@@ -161,6 +161,7 @@
#define SPCMD_SPRW 0x0010 /* SPI Read/Write Access (Dual/Quad) */
#define SPCMD_SSLA(i) ((i) << 4) /* SSL Assert Signal Setting */
#define SPCMD_BRDV_MASK 0x000c /* Bit Rate Division Setting */
+#define SPCMD_BRDV(brdv) ((brdv) << 2)
#define SPCMD_CPOL 0x0002 /* Clock Polarity Setting */
#define SPCMD_CPHA 0x0001 /* Clock Phase Setting */
@@ -242,24 +243,40 @@ struct spi_ops {
int (*transfer_one)(struct spi_controller *ctlr,
struct spi_device *spi, struct spi_transfer *xfer);
u16 extra_mode_bits;
+ u16 min_div;
+ u16 max_div;
u16 flags;
u16 fifo_size;
u8 num_hw_ss;
};
+static void rspi_set_rate(struct rspi_data *rspi)
+{
+ unsigned long clksrc;
+ int brdv = 0, spbr;
+
+ clksrc = clk_get_rate(rspi->clk);
+ spbr = DIV_ROUND_UP(clksrc, 2 * rspi->speed_hz) - 1;
+ while (spbr > 255 && brdv < 3) {
+ brdv++;
+ spbr = DIV_ROUND_UP(spbr + 1, 2) - 1;
+ }
+
+ rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR);
+ rspi->spcmd |= SPCMD_BRDV(brdv);
+ rspi->speed_hz = DIV_ROUND_UP(clksrc, (2U << brdv) * (spbr + 1));
+}
+
/*
* functions for RSPI on legacy SH
*/
static int rspi_set_config_register(struct rspi_data *rspi, int access_size)
{
- int spbr;
-
/* Sets output mode, MOSI signal, and (optionally) loopback */
rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR);
/* Sets transfer bit rate */
- spbr = DIV_ROUND_UP(clk_get_rate(rspi->clk), 2 * rspi->speed_hz) - 1;
- rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR);
+ rspi_set_rate(rspi);
/* Disable dummy transmission, set 16-bit word access, 1 frame */
rspi_write8(rspi, 0, RSPI_SPDCR);
@@ -289,25 +306,11 @@ static int rspi_set_config_register(struct rspi_data *rspi, int access_size)
*/
static int rspi_rz_set_config_register(struct rspi_data *rspi, int access_size)
{
- int spbr;
- int div = 0;
- unsigned long clksrc;
-
/* Sets output mode, MOSI signal, and (optionally) loopback */
rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR);
- clksrc = clk_get_rate(rspi->clk);
- while (div < 3) {
- if (rspi->speed_hz >= clksrc/4) /* 4=(CLK/2)/2 */
- break;
- div++;
- clksrc /= 2;
- }
-
/* Sets transfer bit rate */
- spbr = DIV_ROUND_UP(clksrc, 2 * rspi->speed_hz) - 1;
- rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR);
- rspi->spcmd |= div << 2;
+ rspi_set_rate(rspi);
/* Disable dummy transmission, set byte access */
rspi_write8(rspi, SPDCR_SPLBYTE, RSPI_SPDCR);
@@ -334,14 +337,28 @@ static int rspi_rz_set_config_register(struct rspi_data *rspi, int access_size)
*/
static int qspi_set_config_register(struct rspi_data *rspi, int access_size)
{
- int spbr;
+ unsigned long clksrc;
+ int brdv = 0, spbr;
/* Sets output mode, MOSI signal, and (optionally) loopback */
rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR);
/* Sets transfer bit rate */
- spbr = DIV_ROUND_UP(clk_get_rate(rspi->clk), 2 * rspi->speed_hz);
- rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR);
+ clksrc = clk_get_rate(rspi->clk);
+ if (rspi->speed_hz >= clksrc) {
+ spbr = 0;
+ rspi->speed_hz = clksrc;
+ } else {
+ spbr = DIV_ROUND_UP(clksrc, 2 * rspi->speed_hz);
+ while (spbr > 255 && brdv < 3) {
+ brdv++;
+ spbr = DIV_ROUND_UP(spbr, 2);
+ }
+ spbr = clamp(spbr, 0, 255);
+ rspi->speed_hz = DIV_ROUND_UP(clksrc, (2U << brdv) * spbr);
+ }
+ rspi_write8(rspi, spbr, RSPI_SPBR);
+ rspi->spcmd |= SPCMD_BRDV(brdv);
/* Disable dummy transmission, set byte access */
rspi_write8(rspi, 0, RSPI_SPDCR);
@@ -686,6 +703,8 @@ static int rspi_common_transfer(struct rspi_data *rspi,
{
int ret;
+ xfer->effective_speed_hz = rspi->speed_hz;
+
ret = rspi_dma_check_then_transfer(rspi, xfer);
if (ret != -EAGAIN)
return ret;
@@ -841,6 +860,7 @@ static int qspi_transfer_one(struct spi_controller *ctlr,
{
struct rspi_data *rspi = spi_controller_get_devdata(ctlr);
+ xfer->effective_speed_hz = rspi->speed_hz;
if (spi->mode & SPI_LOOP) {
return qspi_transfer_out_in(rspi, xfer);
} else if (xfer->tx_nbits > SPI_NBITS_SINGLE) {
@@ -1163,6 +1183,8 @@ static int rspi_remove(struct platform_device *pdev)
static const struct spi_ops rspi_ops = {
.set_config_register = rspi_set_config_register,
.transfer_one = rspi_transfer_one,
+ .min_div = 2,
+ .max_div = 4096,
.flags = SPI_CONTROLLER_MUST_TX,
.fifo_size = 8,
.num_hw_ss = 2,
@@ -1171,6 +1193,8 @@ static const struct spi_ops rspi_ops = {
static const struct spi_ops rspi_rz_ops = {
.set_config_register = rspi_rz_set_config_register,
.transfer_one = rspi_rz_transfer_one,
+ .min_div = 2,
+ .max_div = 4096,
.flags = SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX,
.fifo_size = 8, /* 8 for TX, 32 for RX */
.num_hw_ss = 1,
@@ -1181,6 +1205,8 @@ static const struct spi_ops qspi_ops = {
.transfer_one = qspi_transfer_one,
.extra_mode_bits = SPI_TX_DUAL | SPI_TX_QUAD |
SPI_RX_DUAL | SPI_RX_QUAD,
+ .min_div = 1,
+ .max_div = 4080,
.flags = SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX,
.fifo_size = 32,
.num_hw_ss = 1,
@@ -1242,6 +1268,7 @@ static int rspi_probe(struct platform_device *pdev)
int ret;
const struct rspi_plat_data *rspi_pd;
const struct spi_ops *ops;
+ unsigned long clksrc;
ctlr = spi_alloc_master(&pdev->dev, sizeof(struct rspi_data));
if (ctlr == NULL)
@@ -1261,13 +1288,6 @@ static int rspi_probe(struct platform_device *pdev)
ctlr->num_chipselect = 2; /* default */
}
- /* ops parameter check */
- if (!ops->set_config_register) {
- dev_err(&pdev->dev, "there is no set_config_register\n");
- ret = -ENODEV;
- goto error1;
- }
-
rspi = spi_controller_get_devdata(ctlr);
platform_set_drvdata(pdev, rspi);
rspi->ops = ops;
@@ -1301,6 +1321,9 @@ static int rspi_probe(struct platform_device *pdev)
ctlr->unprepare_message = rspi_unprepare_message;
ctlr->mode_bits = SPI_CPHA | SPI_CPOL | SPI_CS_HIGH | SPI_LSB_FIRST |
SPI_LOOP | ops->extra_mode_bits;
+ clksrc = clk_get_rate(rspi->clk);
+ ctlr->min_speed_hz = DIV_ROUND_UP(clksrc, ops->max_div);
+ ctlr->max_speed_hz = DIV_ROUND_UP(clksrc, ops->min_div);
ctlr->flags = ops->flags;
ctlr->dev.of_node = pdev->dev.of_node;
ctlr->use_gpio_descriptors = true;
generated by cgit v1.2.3 (git 2.39.0) at 2024-11-23 10:32:21 +0300