diff options
| author | Sunny Luo <sunny.luo@amlogic.com> | 2020-03-12 14:31:24 +0100 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2020-03-12 17:22:50 +0000 |
| commit | a6cda1f905b4a5442eecce94bda1e136f7e1e539 (patch) | |
| tree | a0ae67c5817c1c02e537d480cfd5506ce898fe97 | |
| parent | b9dfb20eed5c7dab37d6267a985dbe16df9e4293 (diff) | |
spi: meson-spicc: enhance output enable feature
The SPICC controller in Meson-AXG is capable of driving the CLK/MOSI/SS
signal lines through the idle state (between two transmission operation),
which avoid the signals floating in unexpected state.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Yixun Lan <yixun.lan@amlogic.com>
Signed-off-by: Sunny Luo <sunny.luo@amlogic.com>
Link: https://lore.kernel.org/r/20200312133131.26430-3-narmstrong@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
| -rw-r--r-- | drivers/spi/spi-meson-spicc.c | 53 |
1 files changed, 51 insertions, 2 deletions
diff --git a/drivers/spi/spi-meson-spicc.c b/drivers/spi/spi-meson-spicc.c index 8425e5ae1273..ba70ef94a82a 100644 --- a/drivers/spi/spi-meson-spicc.c +++ b/drivers/spi/spi-meson-spicc.c @@ -9,11 +9,13 @@ #include <linux/bitfield.h> #include <linux/clk.h> +#include <linux/clk-provider.h> #include <linux/device.h> #include <linux/io.h> #include <linux/kernel.h> #include <linux/module.h> #include <linux/of.h> +#include <linux/of_device.h> #include <linux/platform_device.h> #include <linux/spi/spi.h> #include <linux/types.h> @@ -113,12 +115,23 @@ #define SPICC_DWADDR 0x24 /* Write Address of DMA */ +#define SPICC_ENH_CTL0 0x38 /* Enhanced Feature */ +#define SPICC_ENH_MOSI_OEN BIT(25) +#define SPICC_ENH_CLK_OEN BIT(26) +#define SPICC_ENH_CS_OEN BIT(27) +#define SPICC_ENH_CLK_CS_DELAY_EN BIT(28) +#define SPICC_ENH_MAIN_CLK_AO BIT(29) + #define writel_bits_relaxed(mask, val, addr) \ writel_relaxed((readl_relaxed(addr) & ~(mask)) | (val), addr) #define SPICC_BURST_MAX 16 #define SPICC_FIFO_HALF 10 +struct meson_spicc_data { + bool has_oen; +}; + struct meson_spicc_device { struct spi_master *master; struct platform_device *pdev; @@ -126,6 +139,7 @@ struct meson_spicc_device { struct clk *core; struct spi_message *message; struct spi_transfer *xfer; + const struct meson_spicc_data *data; u8 *tx_buf; u8 *rx_buf; unsigned int bytes_per_word; @@ -136,6 +150,19 @@ struct meson_spicc_device { bool is_last_burst; }; +static void meson_spicc_oen_enable(struct meson_spicc_device *spicc) +{ + u32 conf; + + if (!spicc->data->has_oen) + return; + + conf = readl_relaxed(spicc->base + SPICC_ENH_CTL0) | + SPICC_ENH_MOSI_OEN | SPICC_ENH_CLK_OEN | SPICC_ENH_CS_OEN; + + writel_relaxed(conf, spicc->base + SPICC_ENH_CTL0); +} + static inline bool meson_spicc_txfull(struct meson_spicc_device *spicc) { return !!FIELD_GET(SPICC_TF, @@ -489,6 +516,13 @@ static int meson_spicc_probe(struct platform_device *pdev) spicc = spi_master_get_devdata(master); spicc->master = master; + spicc->data = of_device_get_match_data(&pdev->dev); + if (!spicc->data) { + dev_err(&pdev->dev, "failed to get match data\n"); + ret = -EINVAL; + goto out_master; + } + spicc->pdev = pdev; platform_set_drvdata(pdev, spicc); @@ -548,6 +582,8 @@ static int meson_spicc_probe(struct platform_device *pdev) else master->max_speed_hz = rate >> 2; + meson_spicc_oen_enable(spicc); + ret = devm_spi_register_master(&pdev->dev, master); if (ret) { dev_err(&pdev->dev, "spi master registration failed\n"); @@ -577,9 +613,22 @@ static int meson_spicc_remove(struct platform_device *pdev) return 0; } +static const struct meson_spicc_data meson_spicc_gx_data = { +}; + +static const struct meson_spicc_data meson_spicc_axg_data = { + .has_oen = true, +}; + static const struct of_device_id meson_spicc_of_match[] = { - { .compatible = "amlogic,meson-gx-spicc", }, - { .compatible = "amlogic,meson-axg-spicc", }, + { + .compatible = "amlogic,meson-gx-spicc", + .data = &meson_spicc_gx_data, + }, + { + .compatible = "amlogic,meson-axg-spicc", + .data = &meson_spicc_axg_data, + }, { /* sentinel */ } }; MODULE_DEVICE_TABLE(of, meson_spicc_of_match); |