[PATCH v1 10/15] phy: cadence-torrent: Add PHY lane reset support

Yuti Amonkar yamonkar at cadence.com
Tue Dec 3 10:13:20 UTC 2019


From: Swapnil Jakhade <sjakhade at cadence.com>

Add reset support for PHY lane group.

Signed-off-by: Swapnil Jakhade <sjakhade at cadence.com>
---
 drivers/phy/cadence/phy-cadence-torrent.c | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/drivers/phy/cadence/phy-cadence-torrent.c b/drivers/phy/cadence/phy-cadence-torrent.c
index 6c3eaaa..ebc3b68 100644
--- a/drivers/phy/cadence/phy-cadence-torrent.c
+++ b/drivers/phy/cadence/phy-cadence-torrent.c
@@ -18,6 +18,7 @@
 #include <linux/of_device.h>
 #include <linux/phy/phy.h>
 #include <linux/platform_device.h>
+#include <linux/reset.h>
 
 #define REF_CLK_19_2MHz		19200000
 #define REF_CLK_25MHz		25000000
@@ -144,6 +145,7 @@ struct cdns_torrent_phy {
 	void __iomem *sd_base; /* SD0801 registers base */
 	u32 num_lanes; /* Number of lanes to use */
 	u32 max_bit_rate; /* Maximum link bit rate to use (in Mbps) */
+	struct reset_control *phy_rst;
 	struct device *dev;
 	struct clk *clk;
 	unsigned long ref_clk_rate;
@@ -182,9 +184,14 @@ static void cdns_dp_phy_write_field(struct cdns_torrent_phy *cdns_phy,
 				    unsigned char num_bits,
 				    unsigned int val);
 
+static int cdns_torrent_phy_on(struct phy *phy);
+static int cdns_torrent_phy_off(struct phy *phy);
+
 static const struct phy_ops cdns_torrent_phy_ops = {
 	.init		= cdns_torrent_dp_init,
 	.exit		= cdns_torrent_dp_exit,
+	.power_on	= cdns_torrent_phy_on,
+	.power_off	= cdns_torrent_phy_off,
 	.owner		= THIS_MODULE,
 };
 
@@ -317,6 +324,9 @@ static int cdns_torrent_dp_init(struct phy *phy)
 
 	/* take out of reset */
 	cdns_dp_phy_write_field(cdns_phy, PHY_RESET, 8, 1, 1);
+
+	cdns_torrent_phy_on(phy);
+
 	ret = cdns_torrent_dp_wait_pma_cmn_ready(cdns_phy);
 	if (ret)
 		return ret;
@@ -945,6 +955,21 @@ static void cdns_dp_phy_write_field(struct cdns_torrent_phy *cdns_phy,
 			      start_bit))));
 }
 
+static int cdns_torrent_phy_on(struct phy *phy)
+{
+	struct cdns_torrent_phy *cdns_phy = phy_get_drvdata(phy);
+
+	/* Take the PHY lane group out of reset */
+	return reset_control_deassert(cdns_phy->phy_rst);
+}
+
+static int cdns_torrent_phy_off(struct phy *phy)
+{
+	struct cdns_torrent_phy *cdns_phy = phy_get_drvdata(phy);
+
+	return reset_control_assert(cdns_phy->phy_rst);
+}
+
 static int cdns_torrent_phy_probe(struct platform_device *pdev)
 {
 	struct resource *regs;
@@ -976,6 +1001,8 @@ static int cdns_torrent_phy_probe(struct platform_device *pdev)
 	if (IS_ERR(cdns_phy->sd_base))
 		return PTR_ERR(cdns_phy->sd_base);
 
+	cdns_phy->phy_rst = devm_reset_control_array_get_exclusive(dev);
+
 	err = device_property_read_u32(dev, "num_lanes",
 				       &cdns_phy->num_lanes);
 	if (err)
-- 
2.7.4



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