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* [PATCH v2] clk-rcar-gen2: RCAN clock support
@ 2014-12-24 22:17 Sergei Shtylyov
  2015-01-05  8:53 ` Laurent Pinchart
                   ` (2 more replies)
  0 siblings, 3 replies; 5+ messages in thread
From: Sergei Shtylyov @ 2014-12-24 22:17 UTC (permalink / raw)
  To: mturquette, linux-kernel, sboyd
  Cc: linux-sh, vksavl, robh+dt, pawel.moll, ijc+devicetree, galak,
	devicetree

Add the RCAN clock support to the R-Car generation 2 CPG driver.  This clock
gets derived from  the USB_EXTAL clock, dividing  it by 6.  The layout of the
RCANCKCR register is similar to those of the clocks supported by the 'clk-div6'
driver but has no divider field, and so can't be supported by that driver...

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>

---
The patch is against the 'clk-next' branch of Mike Turquette's 'linux.git' repo.

Changes in version 2:
- switched to using the composite clock driver with the fixed factor and gated
  clock component drivers;
- removed *static* from 'parent_name' definition, switching from assignment to
  initializer;
- modified the binding document;
- modified the changelog.

 Documentation/devicetree/bindings/clock/renesas,rcar-gen2-cpg-clocks.txt |    5 -
 drivers/clk/shmobile/clk-rcar-gen2.c                                     |   40 ++++++++++
 2 files changed, 43 insertions(+), 2 deletions(-)

Index: linux/Documentation/devicetree/bindings/clock/renesas,rcar-gen2-cpg-clocks.txt
===================================================================
--- linux.orig/Documentation/devicetree/bindings/clock/renesas,rcar-gen2-cpg-clocks.txt
+++ linux/Documentation/devicetree/bindings/clock/renesas,rcar-gen2-cpg-clocks.txt
@@ -16,7 +16,7 @@ Required Properties:
   - clocks: Reference to the parent clock
   - #clock-cells: Must be 1
   - clock-output-names: The names of the clocks. Supported clocks are "main",
-    "pll0", "pll1", "pll3", "lb", "qspi", "sdh", "sd0", "sd1" and "z"
+    "pll0", "pll1", "pll3", "lb", "qspi", "sdh", "sd0", "sd1", "z", and "rcan"
 
 
 Example
@@ -29,5 +29,6 @@ Example
 		clocks = <&extal_clk>;
 		#clock-cells = <1>;
 		clock-output-names = "main", "pll0, "pll1", "pll3",
-				     "lb", "qspi", "sdh", "sd0", "sd1", "z";
+				     "lb", "qspi", "sdh", "sd0", "sd1", "z",
+				     "rcan";
 	};
Index: linux/drivers/clk/shmobile/clk-rcar-gen2.c
===================================================================
--- linux.orig/drivers/clk/shmobile/clk-rcar-gen2.c
+++ linux/drivers/clk/shmobile/clk-rcar-gen2.c
@@ -33,6 +33,7 @@ struct rcar_gen2_cpg {
 #define CPG_FRQCRC			0x000000e0
 #define CPG_FRQCRC_ZFC_MASK		(0x1f << 8)
 #define CPG_FRQCRC_ZFC_SHIFT		8
+#define CPG_RCANCKCR			0x00000270
 
 /* -----------------------------------------------------------------------------
  * Z Clock
@@ -161,6 +162,43 @@ static struct clk * __init cpg_z_clk_reg
 	return clk;
 }
 
+static struct clk * __init cpg_rcan_clk_register(struct rcar_gen2_cpg *cpg,
+						 struct device_node *np)
+{
+	const char *parent_name = of_clk_get_parent_name(np, 1);
+	struct clk_fixed_factor *fixed;
+	struct clk_gate *gate;
+	struct clk *clk;
+
+	fixed = kzalloc(sizeof(*fixed), GFP_KERNEL);
+	if (!fixed)
+		return ERR_PTR(-ENOMEM);
+
+	fixed->mult = 1;
+	fixed->div = 6;
+
+	gate = kzalloc(sizeof(*gate), GFP_KERNEL);
+	if (!gate) {
+		kfree(fixed);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	gate->reg = cpg->reg + CPG_RCANCKCR;
+	gate->bit_idx = 8;
+	gate->flags = CLK_GATE_SET_TO_DISABLE;
+	gate->lock = &cpg->lock;
+
+	clk = clk_register_composite(NULL, "rcan", &parent_name, 1, NULL, NULL,
+				     &fixed->hw, &clk_fixed_factor_ops,
+				     &gate->hw, &clk_gate_ops, 0);
+	if (IS_ERR(clk)) {
+		kfree(gate);
+		kfree(fixed);
+	}
+
+	return clk;
+}
+
 /* -----------------------------------------------------------------------------
  * CPG Clock Data
  */
@@ -263,6 +301,8 @@ rcar_gen2_cpg_register_clock(struct devi
 		shift = 0;
 	} else if (!strcmp(name, "z")) {
 		return cpg_z_clk_register(cpg);
+	} else if (!strcmp(name, "rcan")) {
+		return cpg_rcan_clk_register(cpg, np);
 	} else {
 		return ERR_PTR(-EINVAL);
 	}


^ permalink raw reply	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2015-01-05 13:33 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2014-12-24 22:17 [PATCH v2] clk-rcar-gen2: RCAN clock support Sergei Shtylyov
2015-01-05  8:53 ` Laurent Pinchart
2015-01-05  8:58   ` Laurent Pinchart
2015-01-05 13:23 ` Geert Uytterhoeven
2015-01-05 13:33 ` Geert Uytterhoeven

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