[PATCH v3 7/7] clk: qcom: apcs-msm8916: use clk_parent_data to specify the parent

[Niklas Cassel]

Allow accessing the parent clock names required for the driver
operation by using the device tree node, while falling back to
the previous method of using names in the global name space.

This permits extending the driver to other platforms without having to
modify its source code.

Co-developed-by: Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@xxxxxxxxxx>
Signed-off-by: Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@xxxxxxxxxx>
Signed-off-by: Niklas Cassel <niklas.cassel@xxxxxxxxxx>
---
Changes since v2:
-Use clk_parent_data when specifying clock parents.

 drivers/clk/qcom/apcs-msm8916.c | 23 ++++++++++++++++++-----
 1 file changed, 18 insertions(+), 5 deletions(-)

diff --git a/drivers/clk/qcom/apcs-msm8916.c b/drivers/clk/qcom/apcs-msm8916.c
index 46061b3d230e..bb91644edc00 100644
--- a/drivers/clk/qcom/apcs-msm8916.c
+++ b/drivers/clk/qcom/apcs-msm8916.c
@@ -19,9 +19,9 @@
 
 static const u32 gpll0_a53cc_map[] = { 4, 5 };
 
-static const char * const gpll0_a53cc[] = {
-	"gpll0_vote",
-	"a53pll",
+static const struct clk_parent_data pdata[] = {
+	{ .fw_name = "aux", .name = "gpll0_vote", },
+	{ .fw_name = "pll", .name = "a53pll", },
 };
 
 /*
@@ -51,6 +51,19 @@ static int qcom_apcs_msm8916_clk_probe(struct platform_device *pdev)
 	struct clk_init_data init = { };
 	int ret = -ENODEV;
 
+	/*
+	 * This driver is defined by the devicetree binding
+	 * Documentation/devicetree/bindings/mailbox/qcom,apcs-kpss-global.txt,
+	 * however, this driver is registered as a platform device by
+	 * qcom-apcs-ipc-mailbox.c. Because of this, when this driver
+	 * uses dev_get_regmap() and devm_clk_get(), it has to send the parent
+	 * device as argument.
+	 * When registering with the clock framework, we cannot use this trick,
+	 * since the clock framework always looks at dev->of_node when it tries
+	 * to find parent clock names using clk_parent_data.
+	 */
+	dev->of_node = parent->of_node;
+
 	regmap = dev_get_regmap(parent, NULL);
 	if (!regmap) {
 		dev_err(dev, "failed to get regmap: %d\n", ret);
@@ -62,8 +75,8 @@ static int qcom_apcs_msm8916_clk_probe(struct platform_device *pdev)
 		return -ENOMEM;
 
 	init.name = "a53mux";
-	init.parent_names = gpll0_a53cc;
-	init.num_parents = ARRAY_SIZE(gpll0_a53cc);
+	init.parent_data = pdata;
+	init.num_parents = ARRAY_SIZE(pdata);
 	init.ops = &clk_regmap_mux_div_ops;
 	init.flags = CLK_SET_RATE_PARENT;
 
-- 
2.23.0