From 58c125b9e2b232ce73ed7b24ba7b1ca5ff41c5bd Mon Sep 17 00:00:00 2001 From: Eugeniy Paltsev Date: Thu, 28 Dec 2017 15:09:03 +0300 Subject: DW SPI: Get clock value from Device Tree Add option to set spi controller clock frequency via device tree using standard clock bindings. Define dw_spi_get_clk function as 'weak' as some targets (like SOCFPGA_GEN5 and SOCFPGA_ARRIA10) don't use standard clock API and implement dw_spi_get_clk their own way in their clock manager. Get rid of clock_manager.h include as we don't use cm_get_spi_controller_clk_hz function anymore. (we use redefined dw_spi_get_clk in SOCFPGA clock managers instead) Reviewed-by: Marek Vasut Signed-off-by: Eugeniy Paltsev Reviewed-by: Jagan Teki --- drivers/spi/designware_spi.c | 45 ++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 43 insertions(+), 2 deletions(-) (limited to 'drivers') diff --git a/drivers/spi/designware_spi.c b/drivers/spi/designware_spi.c index 5aa507b2d8..c501aeea16 100644 --- a/drivers/spi/designware_spi.c +++ b/drivers/spi/designware_spi.c @@ -11,6 +11,7 @@ */ #include +#include #include #include #include @@ -18,7 +19,6 @@ #include #include #include -#include DECLARE_GLOBAL_DATA_PTR; @@ -94,6 +94,8 @@ struct dw_spi_priv { void __iomem *regs; unsigned int freq; /* Default frequency */ unsigned int mode; + struct clk clk; + unsigned long bus_clk_rate; int bits_per_word; u8 cs; /* chip select pin */ @@ -176,14 +178,53 @@ static void spi_hw_init(struct dw_spi_priv *priv) debug("%s: fifo_len=%d\n", __func__, priv->fifo_len); } +/* + * We define dw_spi_get_clk function as 'weak' as some targets + * (like SOCFPGA_GEN5 and SOCFPGA_ARRIA10) don't use standard clock API + * and implement dw_spi_get_clk their own way in their clock manager. + */ +__weak int dw_spi_get_clk(struct udevice *bus, ulong *rate) +{ + struct dw_spi_priv *priv = dev_get_priv(bus); + int ret; + + ret = clk_get_by_index(bus, 0, &priv->clk); + if (ret) + return ret; + + ret = clk_enable(&priv->clk); + if (ret && ret != -ENOSYS && ret != -ENOTSUPP) + return ret; + + *rate = clk_get_rate(&priv->clk); + if (!*rate) + goto err_rate; + + debug("%s: get spi controller clk via device tree: %lu Hz\n", + __func__, *rate); + + return 0; + +err_rate: + clk_disable(&priv->clk); + clk_free(&priv->clk); + + return -EINVAL; +} + static int dw_spi_probe(struct udevice *bus) { struct dw_spi_platdata *plat = dev_get_platdata(bus); struct dw_spi_priv *priv = dev_get_priv(bus); + int ret; priv->regs = plat->regs; priv->freq = plat->frequency; + ret = dw_spi_get_clk(bus, &priv->bus_clk_rate); + if (ret) + return ret; + /* Currently only bits_per_word == 8 supported */ priv->bits_per_word = 8; @@ -369,7 +410,7 @@ static int dw_spi_set_speed(struct udevice *bus, uint speed) spi_enable_chip(priv, 0); /* clk_div doesn't support odd number */ - clk_div = cm_get_spi_controller_clk_hz() / speed; + clk_div = priv->bus_clk_rate / speed; clk_div = (clk_div + 1) & 0xfffe; dw_writel(priv, DW_SPI_BAUDR, clk_div); -- cgit