Use clocks subsystem in spi driver.
Signed-off-by: Domen Puncer <[EMAIL PROTECTED]>
---
drivers/spi/mpc52xx_psc_spi.c | 64 +++++++++++++++++++++++++++++++++++++-----
1 files changed, 57 insertions(+), 7 deletions(-)
Index: linux.git/drivers/spi/mpc52xx_psc_spi.c
===================================================================
--- linux.git.orig/drivers/spi/mpc52xx_psc_spi.c
+++ linux.git/drivers/spi/mpc52xx_psc_spi.c
@@ -18,6 +18,7 @@
#if defined(CONFIG_PPC_MERGE)
#include <asm/of_platform.h>
+#include <linux/clk.h>
#else
#include <linux/platform_device.h>
#endif
@@ -53,6 +54,8 @@ struct mpc52xx_psc_spi {
spinlock_t lock;
struct completion done;
+
+ struct clk *clk;
};
/* controller state */
@@ -85,6 +88,13 @@ static void mpc52xx_psc_spi_activate_cs(
u32 sicr;
u16 ccr;
+#ifdef CONFIG_PPC_MERGE
+ u8 bitclkdiv = 2; /* minimum bitclkdiv */
+ int speed = cs->speed_hz ? cs->speed_hz : 1000000;
+ int mclk;
+ int system;
+#endif
+
sicr = in_be32(&psc->sicr);
/* Set clock phase and polarity */
@@ -106,13 +116,39 @@ static void mpc52xx_psc_spi_activate_cs(
/* Set clock frequency and bits per word
* Because psc->ccr is defined as 16bit register instead of 32bit
* just set the lower byte of BitClkDiv
+ * Because BitClkDiv is 8-bit on mpc5200. Lets stay compatible.
*/
ccr = in_be16(&psc->ccr);
ccr &= 0xFF00;
+
+#ifdef CONFIG_PPC_MERGE
+ /*
+ * pscclk = mclk/(bitclkdiv+1)) bitclkdiv is 8-bit, >= 2
+ * mclk = fsys/(mclkdiv+1) mclkdiv is 9-bit, >= 1
+ * as mclkdiv has higher precision, we want is as big as possible
+ * => we get < 0.002*clock error
+ */
+
+ system = clk_get_rate(clk_get_parent(mps->clk));
+ mclk = speed * (bitclkdiv+1);
+ if (system/mclk > 512) { /* bigger than mclkdiv */
+ bitclkdiv = (system/512) / speed;
+ mclk = speed * (bitclkdiv+1);
+ }
+
+ if (clk_set_rate(mps->clk, mclk))
+ dev_err(&spi->dev, "couldn't set psc_mclk's rate\n");
+
+ dev_info(&spi->dev, "clock: wanted: %i, got: %li\n", speed,
+ clk_round_rate(mps->clk, mclk) / (bitclkdiv+1));
+
+ ccr |= bitclkdiv;
+#else
if (cs->speed_hz)
ccr |= (MCLK / cs->speed_hz - 1) & 0xFF;
else /* by default SPI Clk 1MHz */
ccr |= (MCLK / 1000000 - 1) & 0xFF;
+#endif
out_be16(&psc->ccr, ccr);
mps->bits_per_word = cs->bits_per_word;
@@ -330,20 +366,17 @@ static void mpc52xx_psc_spi_cleanup(stru
static int mpc52xx_psc_spi_port_config(int psc_id, struct mpc52xx_psc_spi *mps)
{
+ struct mpc52xx_psc __iomem *psc = mps->psc;
+ int ret = 0;
+
+#if !defined(CONFIG_PPC_MERGE)
struct mpc52xx_cdm __iomem *cdm;
struct mpc52xx_gpio __iomem *gpio;
- struct mpc52xx_psc __iomem *psc = mps->psc;
u32 ul;
u32 mclken_div;
- int ret = 0;
-#if defined(CONFIG_PPC_MERGE)
- cdm = mpc52xx_find_and_map("mpc5200-cdm");
- gpio = mpc52xx_find_and_map("mpc5200-gpio");
-#else
cdm = ioremap(MPC52xx_PA(MPC52xx_CDM_OFFSET), MPC52xx_CDM_SIZE);
gpio = ioremap(MPC52xx_PA(MPC52xx_GPIO_OFFSET), MPC52xx_GPIO_SIZE);
-#endif
if (!cdm || !gpio) {
printk(KERN_ERR "Error mapping CDM/GPIO\n");
ret = -EFAULT;
@@ -399,6 +432,7 @@ static int mpc52xx_psc_spi_port_config(i
ret = -EINVAL;
goto unmap_regs;
}
+#endif
/* Reset the PSC into a known state */
out_8(&psc->command, MPC52xx_PSC_RST_RX);
@@ -422,11 +456,13 @@ static int mpc52xx_psc_spi_port_config(i
mps->bits_per_word = 8;
+#if !defined(CONFIG_PPC_MERGE)
unmap_regs:
if (cdm)
iounmap(cdm);
if (gpio)
iounmap(gpio);
+#endif
return ret;
}
@@ -511,11 +547,22 @@ static int __init mpc52xx_psc_spi_do_pro
ret = spi_register_master(master);
if (ret < 0)
+ goto destr_wq;
+
+#ifdef CONFIG_PPC_MERGE
+ mps->clk = clk_get(dev, "psc_mclk");
+ if (IS_ERR(mps->clk)) {
+ dev_err(dev, "couldn't get psc_mclk clock\n");
+ ret = -ENOENT;
goto unreg_master;
+ }
+#endif
return ret;
unreg_master:
+ spi_unregister_master(master);
+destr_wq:
destroy_workqueue(mps->workqueue);
free_irq:
free_irq(mps->irq, mps);
@@ -532,6 +579,9 @@ static int __exit mpc52xx_psc_spi_do_rem
struct spi_master *master = dev_get_drvdata(dev);
struct mpc52xx_psc_spi *mps = spi_master_get_devdata(master);
+#ifdef CONFIG_PPC_MERGE
+ clk_put(mps->clk);
+#endif
flush_workqueue(mps->workqueue);
destroy_workqueue(mps->workqueue);
spi_unregister_master(master);
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