[PATCH REPOST v6 4/8] clk: scpi: add support for cpufreq virtual device

Sudeep Holla sudeep.holla at arm.com
Wed Sep 16 10:16:35 PDT 2015


The clocks for the CPUs are provided by SCP and are managed by this
clock driver. So the cpufreq device needs to be added only after the
clock get registered and removed when this driver is unloaded.

This patch manages the cpufreq virtual device based on the clock
availability.

Signed-off-by: Sudeep Holla <sudeep.holla at arm.com>
Acked-by: Stephen Boyd <sboyd at codeaurora.org>
Cc: Mike Turquette <mturquette at baylibre.com>
Cc: Liviu Dudau <Liviu.Dudau at arm.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi at arm.com>
Cc: Jon Medhurst (Tixy) <tixy at linaro.org>
Cc: linux-clk at vger.kernel.org
---
 drivers/clk/clk-scpi.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/drivers/clk/clk-scpi.c b/drivers/clk/clk-scpi.c
index e8323db300e2..a201781287b3 100644
--- a/drivers/clk/clk-scpi.c
+++ b/drivers/clk/clk-scpi.c
@@ -34,6 +34,8 @@ struct scpi_clk {
 
 #define to_scpi_clk(clk) container_of(clk, struct scpi_clk, hw)
 
+static struct platform_device *cpufreq_dev;
+
 static unsigned long scpi_clk_recalc_rate(struct clk_hw *hw,
 					  unsigned long parent_rate)
 {
@@ -263,6 +265,11 @@ static int scpi_clocks_remove(struct platform_device *pdev)
 	struct device *dev = &pdev->dev;
 	struct device_node *child, *np = dev->of_node;
 
+	if (cpufreq_dev) {
+		platform_device_unregister(cpufreq_dev);
+		cpufreq_dev = NULL;
+	}
+
 	for_each_available_child_of_node(np, child)
 		of_clk_del_provider(np);
 	return 0;
@@ -288,6 +295,12 @@ static int scpi_clocks_probe(struct platform_device *pdev)
 			return ret;
 		}
 	}
+	/* Add the virtual cpufreq device */
+	cpufreq_dev = platform_device_register_simple("scpi-cpufreq",
+						      -1, NULL, 0);
+	if (!cpufreq_dev)
+		pr_warn("unable to register cpufreq device");
+
 	return 0;
 }
 
-- 
1.9.1




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