[PATCH v1 4/4] spi: npcm-pspi: modify reset support

Tomer Maimon
2020-01-15T17:08:11Z

Modify NPCM perphiral SPI reset support from
direct register access to reset controller support.

Signed-off-by: Tomer Maimon <tmaimon77@gmail.com>
---
drivers/spi/spi-npcm-pspi.c | 33 +++++++++++----------------------
1 file changed, 11 insertions(+), 22 deletions(-)

diff --git a/drivers/spi/spi-npcm-pspi.c b/drivers/spi/spi-npcm-pspi.c
index eac7ba18b4b9..87cd0233c60b 100644
--- a/drivers/spi/spi-npcm-pspi.c
+++ b/drivers/spi/spi-npcm-pspi.c
@@ -12,6 +12,7 @@
#include <linux/spi/spi.h>
#include <linux/gpio.h>
#include <linux/of_gpio.h>
+#include <linux/reset.h>

#include <asm/unaligned.h>

@@ -20,7 +21,7 @@

struct npcm_pspi {
struct completion xfer_done;
- struct regmap *rst_regmap;
+ struct reset_control *reset;
struct spi_master *master;
unsigned int tx_bytes;
unsigned int rx_bytes;
@@ -59,12 +60,6 @@ struct npcm_pspi {
#define NPCM_PSPI_MIN_CLK_DIVIDER 4
#define NPCM_PSPI_DEFAULT_CLK 25000000

-/* reset register */
-#define NPCM7XX_IPSRST2_OFFSET 0x24
-
-#define NPCM7XX_PSPI1_RESET BIT(22)
-#define NPCM7XX_PSPI2_RESET BIT(23)
-
static inline unsigned int bytes_per_word(unsigned int bits)
{
return bits <= 8 ? 1 : 2;
@@ -293,9 +288,9 @@ static int npcm_pspi_unprepare_transfer_hardware(struct spi_master *master)

static void npcm_pspi_reset_hw(struct npcm_pspi *priv)
{
- regmap_write(priv->rst_regmap, NPCM7XX_IPSRST2_OFFSET,
- NPCM7XX_PSPI1_RESET << priv->id);
- regmap_write(priv->rst_regmap, NPCM7XX_IPSRST2_OFFSET, 0x0);
+ reset_control_assert(priv->reset);
+ udelay(5);
+ reset_control_deassert(priv->reset);
}

static irqreturn_t npcm_pspi_handler(int irq, void *dev_id)
@@ -359,10 +354,6 @@ static int npcm_pspi_probe(struct platform_device *pdev)
if (num_cs < 0)
return num_cs;

- pdev->id = of_alias_get_id(np, "spi");
- if (pdev->id < 0)
- pdev->id = 0;
-
master = spi_alloc_master(&pdev->dev, sizeof(*priv));
if (!master)
return -ENOMEM;
@@ -372,7 +363,6 @@ static int npcm_pspi_probe(struct platform_device *pdev)
priv = spi_master_get_devdata(master);
priv->master = master;
priv->is_save_param = false;
- priv->id = pdev->id;

priv->base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(priv->base)) {
@@ -397,11 +387,10 @@ static int npcm_pspi_probe(struct platform_device *pdev)
goto out_disable_clk;
}

- priv->rst_regmap =
- syscon_regmap_lookup_by_compatible("nuvoton,npcm750-rst");
- if (IS_ERR(priv->rst_regmap)) {
- dev_err(&pdev->dev, "failed to find nuvoton,npcm750-rst\n");
- return PTR_ERR(priv->rst_regmap);
+ priv->reset = devm_reset_control_get(&pdev->dev, NULL);
+ if (IS_ERR(priv->reset)) {
+ ret = PTR_ERR(priv->reset);
+ goto out_disable_clk;
}

/* reset SPI-HW block */
@@ -422,7 +411,7 @@ static int npcm_pspi_probe(struct platform_device *pdev)
master->min_speed_hz = DIV_ROUND_UP(clk_hz, NPCM_PSPI_MAX_CLK_DIVIDER);
master->mode_bits = SPI_CPHA | SPI_CPOL;
master->dev.of_node = pdev->dev.of_node;
- master->bus_num = pdev->id;
+ master->bus_num = -1;
master->bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(16);
master->transfer_one = npcm_pspi_transfer_one;
master->prepare_transfer_hardware =
@@ -455,7 +444,7 @@ static int npcm_pspi_probe(struct platform_device *pdev)
if (ret)
goto out_disable_clk;

- pr_info("NPCM Peripheral SPI %d probed\n", pdev->id);
+ pr_info("NPCM Peripheral SPI %d probed\n", master->bus_num);

return 0;

--
2.22.0