[U-Boot] [PATCH 06/10] spi: sun4i: Add CLK support
Jagan Teki
jagan at amarulasolutions.com
Sat Feb 9 13:14:56 UTC 2019
Add CLK support to enable AHB and MOD SPI clocks on sun4i_spi driver.
Note, that the code will enable and disable clock in claim and release
calls to make proper clock and reset handling between claiming and
releasing SPI bus.
Signed-off-by: Jagan Teki <jagan at amarulasolutions.com>
---
drivers/spi/sun4i_spi.c | 56 +++++++++++++++++++++++++++++++++++------
1 file changed, 48 insertions(+), 8 deletions(-)
diff --git a/drivers/spi/sun4i_spi.c b/drivers/spi/sun4i_spi.c
index d3cf25db6f..aeed68764c 100644
--- a/drivers/spi/sun4i_spi.c
+++ b/drivers/spi/sun4i_spi.c
@@ -19,6 +19,7 @@
*/
#include <common.h>
+#include <clk.h>
#include <dm.h>
#include <spi.h>
#include <errno.h>
@@ -29,8 +30,6 @@
#include <asm/gpio.h>
#include <asm/io.h>
-#include <asm/arch/clock.h>
-
#include <linux/iopoll.h>
#define SUN4I_RXDATA_REG 0x00
@@ -133,6 +132,7 @@ struct sun4i_spi_platdata {
struct sun4i_spi_priv {
struct sun4i_spi_variant *variant;
+ struct clk clk_ahb, clk_mod;
u32 base_addr;
u32 freq;
u32 mode;
@@ -263,13 +263,34 @@ static int sun4i_spi_parse_pins(struct udevice *dev)
return 0;
}
-static inline void sun4i_spi_enable_clock(void)
+static inline int sun4i_spi_set_clock(struct udevice *dev, bool enable)
{
- struct sunxi_ccm_reg *const ccm =
- (struct sunxi_ccm_reg *const)SUNXI_CCM_BASE;
+ struct sun4i_spi_priv *priv = dev_get_priv(dev);
+ int ret;
+
+ if (!enable) {
+ clk_disable(&priv->clk_ahb);
+ clk_disable(&priv->clk_mod);
+ return 0;
+ }
- setbits_le32(&ccm->ahb_gate0, (1 << AHB_GATE_OFFSET_SPI0));
- writel((1 << 31), &ccm->spi0_clk_cfg);
+ ret = clk_enable(&priv->clk_ahb);
+ if (ret) {
+ dev_err(dev, "failed to enable ahb clock (ret=%d)\n", ret);
+ return ret;
+ }
+
+ ret = clk_enable(&priv->clk_mod);
+ if (ret) {
+ dev_err(dev, "failed to enable mod clock (ret=%d)\n", ret);
+ goto err_ahb;
+ }
+
+ return 0;
+
+err_ahb:
+ clk_disable(&priv->clk_ahb);
+ return ret;
}
static int sun4i_spi_ofdata_to_platdata(struct udevice *bus)
@@ -293,8 +314,20 @@ static int sun4i_spi_probe(struct udevice *bus)
{
struct sun4i_spi_platdata *plat = dev_get_platdata(bus);
struct sun4i_spi_priv *priv = dev_get_priv(bus);
+ int ret;
+
+ ret = clk_get_by_name(bus, "ahb", &priv->clk_ahb);
+ if (ret) {
+ dev_err(dev, "failed to get ahb clock\n");
+ return ret;
+ }
+
+ ret = clk_get_by_name(bus, "mod", &priv->clk_mod);
+ if (ret) {
+ dev_err(dev, "failed to get mod clock\n");
+ return ret;
+ }
- sun4i_spi_enable_clock();
sun4i_spi_parse_pins(bus);
priv->variant = plat->variant;
@@ -308,6 +341,11 @@ static int sun4i_spi_claim_bus(struct udevice *dev)
{
struct sun4i_spi_priv *priv = dev_get_priv(dev->parent);
struct sun4i_spi_variant *variant = priv->variant;
+ int ret;
+
+ ret = sun4i_spi_set_clock(dev->parent, true);
+ if (ret)
+ return ret;
setbits_le32(priv->base_addr + variant->regs[SPI_GCR],
SUN4I_CTL_ENABLE | SUN4I_CTL_MASTER |
@@ -328,6 +366,8 @@ static int sun4i_spi_release_bus(struct udevice *dev)
clrbits_le32(priv->base_addr + variant->regs[SPI_GCR],
SUN4I_CTL_ENABLE);
+ sun4i_spi_set_clock(dev->parent, false);
+
return 0;
}
--
2.18.0.321.gffc6fa0e3
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