[PATCH 1/2] spi/pxa2xx-pci: Add common clock framework support in PCI glue layer

Chew Chiau Ee chiau.ee.chew at intel.com
Mon Jun 2 12:46:18 PDT 2014


From: Chew, Chiau Ee <chiau.ee.chew at intel.com>

SPI PXA2XX core layer has dependency on common clock framework
to obtain information on host supported clock rate. Thus, we
setup the clock device in the PCI glue layer to enable PCI mode
host pass in the clock rate information.

Signed-off-by: Chew, Chiau Ee <chiau.ee.chew at intel.com>
---
 drivers/spi/spi-pxa2xx-pci.c |   20 ++++++++++++++++++++
 1 files changed, 20 insertions(+), 0 deletions(-)

diff --git a/drivers/spi/spi-pxa2xx-pci.c b/drivers/spi/spi-pxa2xx-pci.c
index c1865c9..11adc9b 100644
--- a/drivers/spi/spi-pxa2xx-pci.c
+++ b/drivers/spi/spi-pxa2xx-pci.c
@@ -7,6 +7,9 @@
 #include <linux/of_device.h>
 #include <linux/module.h>
 #include <linux/spi/pxa2xx_spi.h>
+#include <linux/clk.h>
+#include <linux/clkdev.h>
+#include <linux/clk-provider.h>
 
 enum {
 	PORT_CE4100,
@@ -21,6 +24,7 @@ struct pxa_spi_info {
 	int tx_chan_id;
 	int rx_slave_id;
 	int rx_chan_id;
+	unsigned long max_clk_rate;
 };
 
 static struct pxa_spi_info spi_info_configs[] = {
@@ -32,6 +36,7 @@ static struct pxa_spi_info spi_info_configs[] = {
 		.tx_chan_id = -1,
 		.rx_slave_id = -1,
 		.rx_chan_id = -1,
+		.max_clk_rate = 3686400,
 	},
 	[PORT_BYT] = {
 		.type = LPSS_SSP,
@@ -41,6 +46,7 @@ static struct pxa_spi_info spi_info_configs[] = {
 		.tx_chan_id = 0,
 		.rx_slave_id = 1,
 		.rx_chan_id = 1,
+		.max_clk_rate = 50000000,
 	},
 };
 
@@ -53,6 +59,7 @@ static int pxa2xx_spi_pci_probe(struct pci_dev *dev,
 	struct pxa2xx_spi_master spi_pdata;
 	struct ssp_device *ssp;
 	struct pxa_spi_info *c;
+	struct clk *clk;
 
 	ret = pcim_enable_device(dev);
 	if (ret)
@@ -84,6 +91,19 @@ static int pxa2xx_spi_pci_probe(struct pci_dev *dev,
 	ssp->port_id = (c->port_id >= 0) ? c->port_id : dev->devfn;
 	ssp->type = c->type;
 
+	clk = clk_register_fixed_rate(&dev->dev, "spi_pxa2xx_clk", NULL,
+					CLK_IS_ROOT, c->max_clk_rate);
+	 if (IS_ERR(clk))
+		return PTR_ERR(clk);
+
+	clk_register_clkdev(clk, NULL, dev_name(&dev->dev));
+
+	ssp->clk = devm_clk_get(&dev->dev, NULL);
+	if (IS_ERR(ssp->clk)) {
+		dev_err(&dev->dev, "failed to get clock\n");
+		return PTR_ERR(ssp->clk);
+	}
+
 	memset(&pi, 0, sizeof(pi));
 	pi.parent = &dev->dev;
 	pi.name = "pxa2xx-spi";
-- 
1.7.4.4




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