1 /* 2 * Copyright (c) 2017 BayLibre, SAS. 3 * Author: Jerome Brunet <jbrunet@baylibre.com> 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of version 2 of the GNU General Public License as 7 * published by the Free Software Foundation. 8 * 9 * This program is distributed in the hope that it will be useful, but 10 * WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 12 * General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public License 15 * along with this program; if not, see <http://www.gnu.org/licenses/>. 16 * The full GNU General Public License is included in this distribution 17 * in the file called COPYING. 18 */ 19 20 #include <linux/gpio/consumer.h> 21 #include <linux/module.h> 22 #include <linux/regulator/consumer.h> 23 #include <sound/soc.h> 24 25 #define DRV_NAME "simple-amplifier" 26 27 struct simple_amp { 28 struct gpio_desc *gpiod_enable; 29 }; 30 31 static int drv_event(struct snd_soc_dapm_widget *w, 32 struct snd_kcontrol *control, int event) 33 { 34 struct snd_soc_component *c = snd_soc_dapm_to_component(w->dapm); 35 struct simple_amp *priv = snd_soc_component_get_drvdata(c); 36 int val; 37 38 switch (event) { 39 case SND_SOC_DAPM_POST_PMU: 40 val = 1; 41 break; 42 case SND_SOC_DAPM_PRE_PMD: 43 val = 0; 44 break; 45 default: 46 WARN(1, "Unexpected event"); 47 return -EINVAL; 48 } 49 50 gpiod_set_value_cansleep(priv->gpiod_enable, val); 51 52 return 0; 53 } 54 55 static const struct snd_soc_dapm_widget simple_amp_dapm_widgets[] = { 56 SND_SOC_DAPM_INPUT("INL"), 57 SND_SOC_DAPM_INPUT("INR"), 58 SND_SOC_DAPM_OUT_DRV_E("DRV", SND_SOC_NOPM, 0, 0, NULL, 0, drv_event, 59 (SND_SOC_DAPM_POST_PMU | SND_SOC_DAPM_PRE_PMD)), 60 SND_SOC_DAPM_OUTPUT("OUTL"), 61 SND_SOC_DAPM_OUTPUT("OUTR"), 62 SND_SOC_DAPM_REGULATOR_SUPPLY("VCC", 20, 0), 63 }; 64 65 static const struct snd_soc_dapm_route simple_amp_dapm_routes[] = { 66 { "DRV", NULL, "INL" }, 67 { "DRV", NULL, "INR" }, 68 { "OUTL", NULL, "VCC" }, 69 { "OUTR", NULL, "VCC" }, 70 { "OUTL", NULL, "DRV" }, 71 { "OUTR", NULL, "DRV" }, 72 }; 73 74 static const struct snd_soc_component_driver simple_amp_component_driver = { 75 .dapm_widgets = simple_amp_dapm_widgets, 76 .num_dapm_widgets = ARRAY_SIZE(simple_amp_dapm_widgets), 77 .dapm_routes = simple_amp_dapm_routes, 78 .num_dapm_routes = ARRAY_SIZE(simple_amp_dapm_routes), 79 }; 80 81 static int simple_amp_probe(struct platform_device *pdev) 82 { 83 struct device *dev = &pdev->dev; 84 struct simple_amp *priv; 85 int err; 86 87 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); 88 if (priv == NULL) 89 return -ENOMEM; 90 platform_set_drvdata(pdev, priv); 91 92 priv->gpiod_enable = devm_gpiod_get(dev, "enable", GPIOD_OUT_LOW); 93 if (IS_ERR(priv->gpiod_enable)) { 94 err = PTR_ERR(priv->gpiod_enable); 95 if (err != -EPROBE_DEFER) 96 dev_err(dev, "Failed to get 'enable' gpio: %d", err); 97 return err; 98 } 99 100 return devm_snd_soc_register_component(dev, 101 &simple_amp_component_driver, 102 NULL, 0); 103 } 104 105 #ifdef CONFIG_OF 106 static const struct of_device_id simple_amp_ids[] = { 107 { .compatible = "dioo,dio2125", }, 108 { .compatible = "simple-audio-amplifier", }, 109 { } 110 }; 111 MODULE_DEVICE_TABLE(of, simple_amp_ids); 112 #endif 113 114 static struct platform_driver simple_amp_driver = { 115 .driver = { 116 .name = DRV_NAME, 117 .of_match_table = of_match_ptr(simple_amp_ids), 118 }, 119 .probe = simple_amp_probe, 120 }; 121 122 module_platform_driver(simple_amp_driver); 123 124 MODULE_DESCRIPTION("ASoC Simple Audio Amplifier driver"); 125 MODULE_AUTHOR("Jerome Brunet <jbrunet@baylibre.com>"); 126 MODULE_LICENSE("GPL"); 127