clk: mxs: replace imx23 clk_register_clkdev with clock DT lookup

It really becomes a maintenance issue that every time a device needs
to look up (clk_get) a clock we have to patch kernel clock file to call
clk_register_clkdev for that clock.

Since clock DT support which is meant to resolve clock lookup in device
tree is in place, the patch moves imx23 client devices' clock lookup
over to device tree, so that any new lookup to be added at later time
can just get done in DT instead of kernel.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>

Documentation/devicetree/bindings/clock/imx23-clock.txt

+* Clock bindings for Freescale i.MX23
+
+Required properties:
+- compatible: Should be "fsl,imx23-clkctrl"
+- reg: Address and length of the register set
+- #clock-cells: Should be <1>
+
+The clock consumer should specify the desired clock by having the clock
+ID in its "clocks" phandle cell.  The following is a full list of i.MX23
+clocks and IDs.
+
+	Clock		ID
+	------------------
+	ref_xtal	0
+	pll		1
+	ref_cpu		2
+	ref_emi		3
+	ref_pix		4
+	ref_io		5
+	saif_sel	6
+	lcdif_sel	7
+	gpmi_sel	8
+	ssp_sel		9
+	emi_sel		10
+	cpu		11
+	etm_sel		12
+	cpu_pll		13
+	cpu_xtal	14
+	hbus		15
+	xbus		16
+	lcdif_div	17
+	ssp_div		18
+	gpmi_div	19
+	emi_pll		20
+	emi_xtal	21
+	etm_div		22
+	saif_div	23
+	clk32k_div	24
+	rtc		25
+	adc		26
+	spdif_div	27
+	clk32k		28
+	dri		29
+	pwm		30
+	filt		31
+	uart		32
+	ssp		33
+	gpmi		34
+	spdif		35
+	emi		36
+	saif		37
+	lcdif		38
+	etm		39
+	usb		40
+	usb_pwr		41
+
+Examples:
+
+clks: clkctrl@80040000 {
+	compatible = "fsl,imx23-clkctrl";
+	reg = <0x80040000 0x2000>;
+	#clock-cells = <1>;
+	clock-output-names =
+		...
+		"uart",		/* 32 */
+		...
+		"end_of_list";
+};
+
+auart0: serial@8006c000 {
+	compatible = "fsl,imx23-auart";
+	reg = <0x8006c000 0x2000>;
+	interrupts = <24 25 23>;
+	clocks = <&clks 32>;
+	status = "disabled";
+};

arch/arm/boot/dts/imx23.dtsi

@@ -52,6 +52,7 @@ icoll: interrupt-controller@80000000 {
 			dma-apbh@80004000 {
 				compatible = "fsl,imx23-dma-apbh";
 				reg = <0x80004000 0x2000>;
+				clocks = <&clks 15>;
 			};
 
 			ecc@80008000 {
@@ -67,6 +68,7 @@ gpmi-nand@8000c000 {
 				reg-names = "gpmi-nand", "bch";
 				interrupts = <13>, <56>;
 				interrupt-names = "gpmi-dma", "bch";
+				clocks = <&clks 34>;
 				fsl,gpmi-dma-channel = <4>;
 				status = "disabled";
 			};
@@ -74,6 +76,7 @@ gpmi-nand@8000c000 {
 			ssp0: ssp@80010000 {
 				reg = <0x80010000 0x2000>;
 				interrupts = <15 14>;
+				clocks = <&clks 33>;
 				fsl,ssp-dma-channel = <1>;
 				status = "disabled";
 			};
@@ -290,6 +293,7 @@ emi@80020000 {
 			dma-apbx@80024000 {
 				compatible = "fsl,imx23-dma-apbx";
 				reg = <0x80024000 0x2000>;
+				clocks = <&clks 16>;
 			};
 
 			dcp@80028000 {
@@ -316,12 +320,14 @@ lcdif@80030000 {
 				compatible = "fsl,imx23-lcdif";
 				reg = <0x80030000 2000>;
 				interrupts = <46 45>;
+				clocks = <&clks 38>;
 				status = "disabled";
 			};
 
 			ssp1: ssp@80034000 {
 				reg = <0x80034000 0x2000>;
 				interrupts = <2 20>;
+				clocks = <&clks 33>;
 				fsl,ssp-dma-channel = <2>;
 				status = "disabled";
 			};
@@ -339,9 +345,10 @@ apbx@80040000 {
 			reg = <0x80040000 0x40000>;
 			ranges;
 
-			clkctl@80040000 {
+			clks: clkctrl@80040000 {
+				compatible = "fsl,imx23-clkctrl";
 				reg = <0x80040000 0x2000>;
-				status = "disabled";
+				#clock-cells = <1>;
 			};
 
 			saif0: saif@80042000 {
@@ -393,6 +400,7 @@ rtc@8005c000 {
 			pwm: pwm@80064000 {
 				compatible = "fsl,imx23-pwm";
 				reg = <0x80064000 0x2000>;
+				clocks = <&clks 30>;
 				#pwm-cells = <2>;
 				fsl,pwm-number = <5>;
 				status = "disabled";
@@ -407,6 +415,7 @@ auart0: serial@8006c000 {
 				compatible = "fsl,imx23-auart";
 				reg = <0x8006c000 0x2000>;
 				interrupts = <24 25 23>;
+				clocks = <&clks 32>;
 				status = "disabled";
 			};
 
@@ -414,6 +423,7 @@ auart1: serial@8006e000 {
 				compatible = "fsl,imx23-auart";
 				reg = <0x8006e000 0x2000>;
 				interrupts = <59 60 58>;
+				clocks = <&clks 32>;
 				status = "disabled";
 			};
 
@@ -421,6 +431,8 @@ duart: serial@80070000 {
 				compatible = "arm,pl011", "arm,primecell";
 				reg = <0x80070000 0x2000>;
 				interrupts = <0>;
+				clocks = <&clks 32>, <&clks 16>;
+				clock-names = "uart", "apb_pclk";
 				status = "disabled";
 			};
 

drivers/clk/mxs/clk-imx23.c

@@ -14,6 +14,7 @@
 #include <linux/err.h>
 #include <linux/init.h>
 #include <linux/io.h>
+#include <linux/of.h>
 #include <mach/common.h>
 #include <mach/mx23.h>
 #include "clk.h"
@@ -71,44 +72,6 @@ static void __init clk_misc_init(void)
 	__mxs_setl(30 << BP_FRAC_IOFRAC, FRAC);
 }
 
-static struct clk_lookup uart_lookups[] = {
-	{ .dev_id = "duart", },
-	{ .dev_id = "mxs-auart.0", },
-	{ .dev_id = "mxs-auart.1", },
-	{ .dev_id = "8006c000.serial", },
-	{ .dev_id = "8006e000.serial", },
-	{ .dev_id = "80070000.serial", },
-};
-
-static struct clk_lookup hbus_lookups[] = {
-	{ .dev_id = "imx23-dma-apbh", },
-	{ .dev_id = "80004000.dma-apbh", },
-};
-
-static struct clk_lookup xbus_lookups[] = {
-	{ .dev_id = "duart", .con_id = "apb_pclk"},
-	{ .dev_id = "80070000.serial", .con_id = "apb_pclk"},
-	{ .dev_id = "imx23-dma-apbx", },
-	{ .dev_id = "80024000.dma-apbx", },
-};
-
-static struct clk_lookup ssp_lookups[] = {
-	{ .dev_id = "imx23-mmc.0", },
-	{ .dev_id = "imx23-mmc.1", },
-	{ .dev_id = "80010000.ssp", },
-	{ .dev_id = "80034000.ssp", },
-};
-
-static struct clk_lookup lcdif_lookups[] = {
-	{ .dev_id = "imx23-fb", },
-	{ .dev_id = "80030000.lcdif", },
-};
-
-static struct clk_lookup gpmi_lookups[] = {
-	{ .dev_id = "imx23-gpmi-nand", },
-	{ .dev_id = "8000c000.gpmi-nand", },
-};
-
 static const char *sel_pll[]  __initconst = { "pll", "ref_xtal", };
 static const char *sel_cpu[]  __initconst = { "ref_cpu", "ref_xtal", };
 static const char *sel_pix[]  __initconst = { "ref_pix", "ref_xtal", };
@@ -127,6 +90,7 @@ enum imx23_clk {
 };
 
 static struct clk *clks[clk_max];
+static struct clk_onecell_data clk_data;
 
 static enum imx23_clk clks_init_on[] __initdata = {
 	cpu, hbus, xbus, emi, uart,
@@ -134,6 +98,7 @@ static enum imx23_clk clks_init_on[] __initdata = {
 
 int __init mx23_clocks_init(void)
 {
+	struct device_node *np;
 	int i;
 
 	clk_misc_init();
@@ -188,14 +153,14 @@ int __init mx23_clocks_init(void)
 			return PTR_ERR(clks[i]);
 		}
 
+	np = of_find_compatible_node(NULL, NULL, "fsl,imx23-clkctrl");
+	if (np) {
+		clk_data.clks = clks;
+		clk_data.clk_num = ARRAY_SIZE(clks);
+		of_clk_add_provider(np, of_clk_src_onecell_get, &clk_data);
+	}
+
 	clk_register_clkdev(clks[clk32k], NULL, "timrot");
-	clk_register_clkdev(clks[pwm], NULL, "80064000.pwm");
-	clk_register_clkdevs(clks[hbus], hbus_lookups, ARRAY_SIZE(hbus_lookups));
-	clk_register_clkdevs(clks[xbus], xbus_lookups, ARRAY_SIZE(xbus_lookups));
-	clk_register_clkdevs(clks[uart], uart_lookups, ARRAY_SIZE(uart_lookups));
-	clk_register_clkdevs(clks[ssp], ssp_lookups, ARRAY_SIZE(ssp_lookups));
-	clk_register_clkdevs(clks[gpmi], gpmi_lookups, ARRAY_SIZE(gpmi_lookups));
-	clk_register_clkdevs(clks[lcdif], lcdif_lookups, ARRAY_SIZE(lcdif_lookups));
 
 	for (i = 0; i < ARRAY_SIZE(clks_init_on); i++)
 		clk_prepare_enable(clks[clks_init_on[i]]);