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From b0fde8ea889e47505e4112d89da4be9469a37775 Mon Sep 17 00:00:00 2001
From: Eric Anholt <eric@anholt.net>
Date: Thu, 14 Apr 2016 15:13:53 -0700
Subject: [PATCH] clk: bcm2835: Do appropriate name lookups for DSI1's parents
as well.
Signed-off-by: Eric Anholt <eric@anholt.net>
---
.../bindings/clock/brcm,bcm2835-cprman.txt | 12 ++++-
drivers/clk/bcm/clk-bcm2835.c | 54 +++++++++++++++++-----
2 files changed, 54 insertions(+), 12 deletions(-)
--- a/Documentation/devicetree/bindings/clock/brcm,bcm2835-cprman.txt
+++ b/Documentation/devicetree/bindings/clock/brcm,bcm2835-cprman.txt
@@ -16,7 +16,17 @@ Required properties:
- #clock-cells: Should be <1>. The permitted clock-specifier values can be
found in include/dt-bindings/clock/bcm2835.h
- reg: Specifies base physical address and size of the registers
-- clocks: The external oscillator clock phandle
+- clocks: phandles to the parent clocks used as input to the module, in
+ the following order:
+
+ - External oscillator
+ - DSI1 byte clock
+ - DSI1 DDR2 clock
+ - DSI1 DDR clock
+
+ Only external oscillator is required. The DSI clocks may
+ not be present, in which case their children will be
+ unusable.
Example:
--- a/drivers/clk/bcm/clk-bcm2835.c
+++ b/drivers/clk/bcm/clk-bcm2835.c
@@ -297,11 +297,29 @@
#define LOCK_TIMEOUT_NS 100000000
#define BCM2835_MAX_FB_RATE 1750000000u
+/*
+ * Names of clocks used within the driver that need to be replaced
+ * with an external parent's name. This array is in the order that
+ * the clocks node in the DT references external clocks.
+ */
+static const char *cprman_parent_names[] = {
+ "xosc",
+ "dsi1_byte",
+ "dsi1_ddr2",
+ "dsi1_ddr",
+};
+
struct bcm2835_cprman {
struct device *dev;
void __iomem *regs;
spinlock_t regs_lock; /* spinlock for all clocks */
- const char *osc_name;
+
+ /*
+ * Real names of cprman clock parents looked up through
+ * of_clk_get_parent_name(), which will be used in the
+ * parent_names[] arrays for clock registration.
+ */
+ const char *real_parent_names[ARRAY_SIZE(cprman_parent_names)];
struct clk_onecell_data onecell;
struct clk *clks[];
@@ -1168,7 +1186,7 @@ static struct clk *bcm2835_register_pll(
memset(&init, 0, sizeof(init));
/* All of the PLLs derive from the external oscillator. */
- init.parent_names = &cprman->osc_name;
+ init.parent_names = &cprman->real_parent_names[0];
init.num_parents = 1;
init.name = data->name;
init.ops = &bcm2835_pll_clk_ops;
@@ -1251,17 +1269,21 @@ static struct clk *bcm2835_register_cloc
struct bcm2835_clock *clock;
struct clk_init_data init;
const char *parents[1 << CM_SRC_BITS];
- size_t i;
+ size_t i, j;
/*
- * Replace our "xosc" references with the oscillator's
- * actual name.
+ * Replace our strings referencing parent clocks with the
+ * actual clock-output-name of the parent.
*/
for (i = 0; i < data->num_mux_parents; i++) {
- if (strcmp(data->parents[i], "xosc") == 0)
- parents[i] = cprman->osc_name;
- else
- parents[i] = data->parents[i];
+ parents[i] = data->parents[i];
+
+ for (j = 0; j < ARRAY_SIZE(cprman_parent_names); j++) {
+ if (strcmp(parents[i], cprman_parent_names[j]) == 0) {
+ parents[i] = cprman->real_parent_names[j];
+ break;
+ }
+ }
}
memset(&init, 0, sizeof(init));
@@ -1883,8 +1905,18 @@ static int bcm2835_clk_probe(struct plat
if (IS_ERR(cprman->regs))
return PTR_ERR(cprman->regs);
- cprman->osc_name = of_clk_get_parent_name(dev->of_node, 0);
- if (!cprman->osc_name)
+ for (i = 0; i < ARRAY_SIZE(cprman_parent_names); i++) {
+ cprman->real_parent_names[i] =
+ of_clk_get_parent_name(dev->of_node, i);
+ }
+ /*
+ * Make sure the external oscillator has been registered.
+ *
+ * The other (DSI) clocks are not present on older device
+ * trees, which we still need to support for backwards
+ * compatibility.
+ */
+ if (!cprman->real_parent_names[0])
return -ENODEV;
platform_set_drvdata(pdev, cprman);
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