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Subject[PATCH V3 4/4] PCI: exynos: support the using PHY generic framework
Date
Switch the pci-exynos driver to generic PHY framework. At the same time
backward compatibility is preserved: Warning will be printed for old
DTB.

Refer to the binding file:
- Documentation/devictree/bindings/pci/samsung,exynos5440-pcie.txt

Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
Acked-by: Krzysztof Kozlowski <krzk@kernel.org>
Acked-by: Jingoo Han <jingoohan1@gmail.com>
Reviewed-by: Pankaj Dubey <pankaj.dubey@samsung.com>
Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>
---
Changelog on V3:
- Changes the commit-message
- Fixes the merge conflict

Changelog on V2:
- This patch is split from previous PATCH[1/4]
- Maintain the backward compatibility
- Adds 'using_phy' for cheching whether phy framework is used or not
- Adds 'DEPRECATED' message for old dt-binding way

drivers/pci/host/pci-exynos.c | 54 +++++++++++++++++++++++++++++++++++++++----
1 file changed, 50 insertions(+), 4 deletions(-)

diff --git a/drivers/pci/host/pci-exynos.c b/drivers/pci/host/pci-exynos.c
index 758906b..f6a8b6e 100644
--- a/drivers/pci/host/pci-exynos.c
+++ b/drivers/pci/host/pci-exynos.c
@@ -21,6 +21,7 @@
#include <linux/of_gpio.h>
#include <linux/pci.h>
#include <linux/platform_device.h>
+#include <linux/phy/phy.h>
#include <linux/resource.h>
#include <linux/signal.h>
#include <linux/types.h>
@@ -110,6 +111,10 @@ struct exynos_pcie {
struct exynos_pcie_clk_res *clk_res;
const struct exynos_pcie_ops *ops;
int reset_gpio;
+
+ /* For Generic PHY Framework */
+ bool using_phy;
+ struct phy *phy;
};

struct exynos_pcie_ops {
@@ -126,6 +131,10 @@ static int exynos5440_pcie_get_mem_resources(struct platform_device *pdev,
struct resource *res;
struct device *dev = ep->pp.dev;

+ /* If using the PHY framework, doesn't need to get other resource */
+ if (ep->using_phy)
+ return 0;
+
ep->mem_res = devm_kzalloc(dev, sizeof(*ep->mem_res), GFP_KERNEL);
if (!ep->mem_res)
return -ENOMEM;
@@ -396,10 +405,28 @@ static int exynos_pcie_establish_link(struct exynos_pcie *ep)
}

exynos_pcie_assert_core_reset(ep);
- exynos_pcie_assert_phy_reset(ep);
- exynos_pcie_deassert_phy_reset(ep);
- exynos_pcie_power_on_phy(ep);
- exynos_pcie_init_phy(ep);
+
+ if (ep->using_phy) {
+ phy_reset(ep->phy);
+
+ exynos_pcie_writel(ep->mem_res->elbi_base, 1,
+ PCIE_PWR_RESET);
+
+ phy_power_on(ep->phy);
+ phy_init(ep->phy);
+ } else {
+ exynos_pcie_assert_phy_reset(ep);
+ exynos_pcie_deassert_phy_reset(ep);
+ exynos_pcie_power_on_phy(ep);
+ exynos_pcie_init_phy(ep);
+
+ /* pulse for common reset */
+ exynos_pcie_writel(ep->mem_res->block_base, 1,
+ PCIE_PHY_COMMON_RESET);
+ udelay(500);
+ exynos_pcie_writel(ep->mem_res->block_base, 0,
+ PCIE_PHY_COMMON_RESET);
+ }

/* pulse for common reset */
exynos_pcie_writel(ep->mem_res->block_base, 1, PCIE_PHY_COMMON_RESET);
@@ -418,6 +445,11 @@ static int exynos_pcie_establish_link(struct exynos_pcie *ep)
if (!dw_pcie_wait_for_link(pp))
return 0;

+ if (ep->using_phy) {
+ phy_power_off(ep->phy);
+ return -ETIMEDOUT;
+ }
+
while (exynos_pcie_readl(ep->mem_res->phy_base,
PCIE_PHY_PLL_LOCKED) == 0) {
val = exynos_pcie_readl(ep->mem_res->block_base,
@@ -624,6 +656,17 @@ static int __init exynos_pcie_probe(struct platform_device *pdev)

ep->reset_gpio = of_get_named_gpio(np, "reset-gpio", 0);

+ /* Assume that controller doesn't use the PHY framework */
+ ep->using_phy = false;
+
+ ep->phy = devm_of_phy_get(dev, np, NULL);
+ if (IS_ERR(ep->phy)) {
+ if (PTR_ERR(ep->phy) == -EPROBE_DEFER)
+ return PTR_ERR(ep->phy);
+ dev_warn(dev, "Use the 'phy' property. Current DT of pci-exynos was deprecated!!\n");
+ } else
+ ep->using_phy = true;
+
if (ep->ops && ep->ops->get_mem_resources) {
ret = ep->ops->get_mem_resources(pdev, ep);
if (ret)
@@ -647,6 +690,9 @@ static int __init exynos_pcie_probe(struct platform_device *pdev)
return 0;

fail_probe:
+ if (ep->using_phy)
+ phy_exit(ep->phy);
+
if (ep->ops && ep->ops->deinit_clk_resources)
ep->ops->deinit_clk_resources(ep);
return ret;
--
2.10.2
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