test: panel: Add a test for the panel uclass

At present this uclass has no tests. Add a simple one which checks the PWM
configuration, regulator and GPIO.

Signed-off-by: Simon Glass <sjg@chromium.org>

arch/sandbox/dts/sandbox_pmic.dtsi

@@ -60,7 +60,7 @@
 		regulator-max-microvolt = <3300000>;
 	};
 
-	ldo1 {
+	ldo_1: ldo1 {
 		regulator-name = "VDD_EMMC_1.8V";
 		regulator-min-microvolt = <1800000>;
 		regulator-max-microvolt = <1800000>;

arch/sandbox/dts/test.dts

@@ -11,6 +11,8 @@
 		eth0 = "/eth@10002000";
 		eth3 = &eth_3;
 		eth5 = &eth_5;
+		gpio1 = &gpio_a;
+		gpio2 = &gpio_b;
 		i2c0 = "/i2c@0";
 		mmc0 = "/mmc0";
 		mmc1 = "/mmc1";
@@ -91,6 +93,15 @@
 		reg = <2 1>;
 	};
 
+	backlight: backlight {
+		compatible = "pwm-backlight";
+		enable-gpios = <&gpio_a 1>;
+		power-supply = <&ldo_1>;
+		pwms = <&pwm 0 1000>;
+		default-brightness-level = <5>;
+		brightness-levels = <0 16 32 64 128 170 202 234 255>;
+	};
+
 	bind-test {
 		bind-test-child1 {
 			compatible = "sandbox,phy";
@@ -441,12 +452,14 @@
 		power-domains = <&pwrdom 2>;
 	};
 
-	pwm {
+	pwm: pwm {
 		compatible = "sandbox,pwm";
+		#pwm-cells = <2>;
 	};
 
 	pwm2 {
 		compatible = "sandbox,pwm";
+		#pwm-cells = <2>;
 	};
 
 	ram {
@@ -483,6 +496,11 @@
 		remoteproc-name = "remoteproc-test-dev2";
 	};
 
+	panel {
+		compatible = "simple-panel";
+		backlight = <&backlight 0 100>;
+	};
+
 	smem@0 {
 		compatible = "sandbox,smem";
 	};

arch/sandbox/include/asm/test.h

@@ -98,4 +98,19 @@ int sandbox_usb_keyb_add_string(struct udevice *dev, const char *str);
  * @buflen:	length of buffer in bytes
  */
 int sandbox_osd_get_mem(struct udevice *dev, u8 *buf, size_t buflen);
+
+/**
+ * sandbox_pwm_get_config() - get the PWM config for a channel
+ *
+ * @dev: Device to check
+ * @channel: Channel number to check
+ * @period_ns: Period of the PWM in nanoseconds
+ * @duty_ns: Current duty cycle of the PWM in nanoseconds
+ * @enable: true if the PWM is enabled
+ * @polarity: true if the PWM polarity is active high
+ * @return 0 if OK, -ENOSPC if the PWM number is invalid
+ */
+int sandbox_pwm_get_config(struct udevice *dev, uint channel, uint *period_nsp,
+			   uint *duty_nsp, bool *enablep, bool *polarityp);
+
 #endif

drivers/pwm/sandbox_pwm.c

@@ -14,6 +14,14 @@ enum {
 	NUM_CHANNELS	= 3,
 };
 
+/**
+ * struct sandbox_pwm_chan - a sandbox PWM channel
+ *
+ * @period_ns: Period of the PWM in nanoseconds
+ * @duty_ns: Current duty cycle of the PWM in nanoseconds
+ * @enable: true if the PWM is enabled
+ * @polarity: true if the PWM polarity is active high
+ */
 struct sandbox_pwm_chan {
 	uint period_ns;
 	uint duty_ns;
@@ -25,6 +33,23 @@ struct sandbox_pwm_priv {
 	struct sandbox_pwm_chan chan[NUM_CHANNELS];
 };
 
+int sandbox_pwm_get_config(struct udevice *dev, uint channel, uint *period_nsp,
+			   uint *duty_nsp, bool *enablep, bool *polarityp)
+{
+	struct sandbox_pwm_priv *priv = dev_get_priv(dev);
+	struct sandbox_pwm_chan *chan;
+
+	if (channel >= NUM_CHANNELS)
+		return -ENOSPC;
+	chan = &priv->chan[channel];
+	*period_nsp = chan->period_ns;
+	*duty_nsp = chan->duty_ns;
+	*enablep = chan->enable;
+	*polarityp = chan->polarity;
+
+	return 0;
+}
+
 static int sandbox_pwm_set_config(struct udevice *dev, uint channel,
 				  uint period_ns, uint duty_ns)
 {

test/dm/Makefile

@@ -25,6 +25,7 @@ obj-$(CONFIG_DM_MAILBOX) += mailbox.o
 obj-$(CONFIG_DM_MMC) += mmc.o
 obj-y += ofnode.o
 obj-$(CONFIG_OSD) += osd.o
+obj-$(CONFIG_DM_VIDEO) += panel.o
 obj-$(CONFIG_DM_PCI) += pci.o
 obj-$(CONFIG_PHY) += phy.o
 obj-$(CONFIG_POWER_DOMAIN) += power-domain.o

test/dm/panel.c

@@ -0,0 +1,50 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Test for panel uclass
+ *
+ * Copyright (c) 2018 Google, Inc
+ * Written by Simon Glass <sjg@chromium.org>
+ */
+
+#include <common.h>
+#include <backlight.h>
+#include <dm.h>
+#include <panel.h>
+#include <video.h>
+#include <asm/gpio.h>
+#include <asm/test.h>
+#include <dm/test.h>
+#include <test/ut.h>
+#include <power/regulator.h>
+
+/* Basic test of the panel uclass */
+static int dm_test_panel(struct unit_test_state *uts)
+{
+	struct udevice *dev, *pwm, *gpio, *reg;
+	uint period_ns;
+	uint duty_ns;
+	bool enable;
+	bool polarity;
+
+	ut_assertok(uclass_first_device_err(UCLASS_PANEL, &dev));
+	ut_assertok(uclass_first_device_err(UCLASS_PWM, &pwm));
+	ut_assertok(uclass_get_device(UCLASS_GPIO, 1, &gpio));
+	ut_assertok(regulator_get_by_platname("VDD_EMMC_1.8V", &reg));
+	ut_assertok(sandbox_pwm_get_config(pwm, 0, &period_ns, &duty_ns,
+					   &enable, &polarity));
+	ut_asserteq(false, enable);
+	ut_asserteq(false, regulator_get_enable(reg));
+
+	ut_assertok(panel_enable_backlight(dev));
+	ut_assertok(sandbox_pwm_get_config(pwm, 0, &period_ns, &duty_ns,
+					   &enable, &polarity));
+	ut_asserteq(1000, period_ns);
+	ut_asserteq(170 * 1000 / 256, duty_ns);
+	ut_asserteq(true, enable);
+	ut_asserteq(false, polarity);
+	ut_asserteq(1, sandbox_gpio_get_value(gpio, 1));
+	ut_asserteq(true, regulator_get_enable(reg));
+
+	return 0;
+}
+DM_TEST(dm_test_panel, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);