Initial bringup for FM elan module & use fm_ctrl.ko

As request from RF team, for fmradio signal lose issue in new HW design,
need to add elna module for ensure fmradio performance.

Change-Id: I9c21f63788fbef4c28785e9d985631f1ef248105
Reviewed-on: https://gerrit.mot.com/1376704
SME-Granted: SME Approvals Granted
SLTApproved: Slta Waiver
Tested-by: Jira Key
Reviewed-by: Qiu Feng <fengqiu1@lenovo.com>
Reviewed-by: Tao Sun <suntao2@motorola.com>
Submit-Approved: Jira Key

drivers/fm/Android.mk

@@ -0,0 +1,10 @@
+ifeq ($(BOARD_HAS_FM_ELNA), true)
+DLKM_DIR := motorola/kernel/modules
+LOCAL_PATH := $(call my-dir)
+
+include $(CLEAR_VARS)
+LOCAL_MODULE := fm_ctrl.ko
+LOCAL_MODULE_TAGS := optional
+LOCAL_MODULE_PATH := $(KERNEL_MODULES_OUT)
+include $(DLKM_DIR)/AndroidKernelModule.mk
+endif

drivers/fm/Kbuild

@@ -0,0 +1,4 @@
+# add -Wall to try to catch everything we can.
+EXTRA_CFLAGS += -Wall
+
+obj-m += fm_ctrl.o

drivers/fm/Makefile

@@ -0,0 +1,11 @@
+KERNEL_SRC ?= /lib/modules/$(shell uname -r)/build
+
+all:
+	$(MAKE) -C $(KERNEL_SRC) M=$(shell pwd) modules $(KBUILD_OPTIONS)
+
+modules_install:
+	$(MAKE) INSTALL_MOD_STRIP=1 -C $(KERNEL_SRC) M=$(shell pwd) modules_install
+
+clean:
+	$(MAKE) -C $(KERNEL_SRC) M=$(PWD) clean
+

drivers/fm/fm_ctrl.c

@@ -0,0 +1,199 @@
+/*
+ * Copyright (C) 2019 Motorola Mobility LLC
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/version.h>
+#include <linux/init.h>
+#include <linux/uaccess.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/platform_device.h>
+
+#define DRIVER_VERSION "0.0.1"
+
+struct fm_ctrl_drvdata {
+	struct device	*dev;
+	struct pinctrl *pinctrl;
+	struct pinctrl_state *pstate_default;
+	struct pinctrl_state *pstate_active;
+	struct pinctrl_state *pstate_suspend;
+};
+
+static ssize_t device_name_read(struct device *dev,
+				    struct device_attribute *attr,
+				    char *buf)
+{
+	struct fm_ctrl_drvdata *data = dev_get_drvdata(dev);
+
+	if (!data) {
+		pr_err("fm_ctrl drvdata is NULL\n");
+		return -EINVAL;
+	}
+
+	return snprintf(buf, PAGE_SIZE, "moto fm control intf\n");
+}
+
+
+static ssize_t elna_en_read(struct device *dev,
+				 struct device_attribute *attr,
+				 char *buf)
+{
+	struct fm_ctrl_drvdata *data = dev_get_drvdata(dev);
+
+	if (!data) {
+		pr_err("fm_ctrl drvdata is NULL\n");
+		return -EINVAL;
+	}
+
+	return snprintf(buf, PAGE_SIZE, "fm_ctrl: not support!\n");
+}
+
+static ssize_t elna_en_write(struct device *dev,
+				 struct device_attribute *attr,
+				 const char *buf,
+				 size_t count)
+{
+	struct fm_ctrl_drvdata *data = dev_get_drvdata(dev);
+	int ret = 0;
+	unsigned int res = 0;
+
+	if (!data) {
+		pr_err("fm_ctrl drvdata is NULL\n");
+		return -EINVAL;
+	}
+
+	ret = kstrtouint(buf, 0, &res);
+	if(ret) {
+		pr_err("fm_ctrl failed to get data, set as default!\n");
+	}
+	if(1 == res) {
+		ret = pinctrl_select_state(data->pinctrl, data->pstate_active);
+	}
+	else {
+		ret = pinctrl_select_state(data->pinctrl, data->pstate_suspend);
+	}
+	if(ret) {
+		pr_err("fm_ctrl failed to set pinctrl!\n");
+	}
+	else {
+		pr_info("fm_ctrl set elan=%u\n", res);
+	}
+
+	return count;
+}
+
+
+static DEVICE_ATTR(device_name, 0444, device_name_read, NULL);
+static DEVICE_ATTR(elna_en, 0644, elna_en_read, elna_en_write);
+
+static struct attribute *fm_ctrl_sysfs_attrs[] = {
+	&dev_attr_device_name.attr,
+	&dev_attr_elna_en.attr,
+	NULL,
+};
+
+static struct attribute_group fm_ctrl_sysfs_attr_grp = {
+	.attrs = fm_ctrl_sysfs_attrs,
+};
+
+
+static int fm_ctrl_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct fm_ctrl_drvdata *drvdata;
+	int ret = 0;
+
+	dev_dbg(&pdev->dev, "%s begin\n", __func__);
+	drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
+	if (!drvdata)
+		return -ENOMEM;
+
+	drvdata->dev = &pdev->dev;
+	platform_set_drvdata(pdev, drvdata);
+
+	/* Get pinctrl if target uses pinctrl */
+	drvdata->pinctrl = devm_pinctrl_get(dev);
+	if (IS_ERR_OR_NULL(drvdata->pinctrl)) {
+		ret = PTR_ERR(drvdata->pinctrl);
+		pr_err("%s: Pincontrol DT property returned %X\n", __func__, ret);
+		return ret;
+	}
+
+	drvdata->pstate_default = pinctrl_lookup_state(drvdata->pinctrl,
+		"default");
+	if (IS_ERR_OR_NULL(drvdata->pstate_default)) {
+		ret = PTR_ERR(drvdata->pstate_default);
+		pr_err("Can not lookup default pinstate %d\n", ret);
+		return -ENOENT;
+	}
+	drvdata->pstate_active = pinctrl_lookup_state(drvdata->pinctrl,
+		"elna_active");
+	if (IS_ERR_OR_NULL(drvdata->pstate_active)) {
+		ret = PTR_ERR(drvdata->pstate_active);
+		pr_err("Can not lookup active pinstate %d\n", ret);
+		return ret;
+	}
+	drvdata->pstate_suspend = pinctrl_lookup_state(drvdata->pinctrl,
+		"elna_suspend");
+	if (IS_ERR_OR_NULL(drvdata->pstate_suspend)) {
+		ret = PTR_ERR(drvdata->pstate_suspend);
+		pr_err("Can not lookup suspend pinstate %d\n", ret);
+		return ret;
+	}
+
+	ret = sysfs_create_group(&dev->kobj, &fm_ctrl_sysfs_attr_grp);
+	if (ret) {
+		pr_err("%s: sysfs group creation failed %d\n", __func__, ret);
+		return ret;
+	}
+
+	device_init_wakeup(&pdev->dev, 1);
+	dev_info(&pdev->dev, "probe: All success !\n");
+
+	return ret;
+}
+
+static int fm_ctrl_remove(struct platform_device *pdev)
+{
+	device_init_wakeup(&pdev->dev, 0);
+	return 0;
+}
+
+
+static const struct of_device_id fm_ctrl_match[] = {
+	{ .compatible = "moto,fmctrl" },
+	{}
+};
+
+static struct platform_driver fm_ctrl_plat_driver = {
+	.probe = fm_ctrl_probe,
+	.remove = fm_ctrl_remove,
+	.driver = {
+		.name = "fm_ctrl",
+		.owner = THIS_MODULE,
+		.of_match_table = fm_ctrl_match,
+	},
+};
+
+module_platform_driver(fm_ctrl_plat_driver);
+
+
+MODULE_AUTHOR("Motorola Mobiity");
+MODULE_DESCRIPTION("FMRadio control interface driver");
+MODULE_VERSION(DRIVER_VERSION);
+MODULE_LICENSE("GPL");