1// SPDX-License-Identifier: GPL-2.0
  2//
  3// Copyright (C) 2019 Texas Instruments Incorporated - http://www.ti.com/
  4// Author: Vignesh Raghavendra <vigneshr@ti.com>
  5
  6#include <linux/err.h>
  7#include <linux/kernel.h>
  8#include <linux/module.h>
  9#include <linux/mtd/cfi.h>
 10#include <linux/mtd/hyperbus.h>
 11#include <linux/mtd/mtd.h>
 12#include <linux/mux/consumer.h>
 13#include <linux/of.h>
 14#include <linux/platform_device.h>
 15#include <linux/pm_runtime.h>
 16#include <linux/types.h>
 17
 18#define AM654_HBMC_CALIB_COUNT 25
 19
 20struct am654_hbmc_priv {
 21	struct hyperbus_ctlr ctlr;
 22	struct hyperbus_device hbdev;
 23	struct mux_control *mux_ctrl;
 24};
 25
 26static int am654_hbmc_calibrate(struct hyperbus_device *hbdev)
 27{
 28	struct map_info *map = &hbdev->map;
 29	struct cfi_private cfi;
 30	int count = AM654_HBMC_CALIB_COUNT;
 31	int pass_count = 0;
 32	int ret;
 33
 34	cfi.interleave = 1;
 35	cfi.device_type = CFI_DEVICETYPE_X16;
 36	cfi_send_gen_cmd(0xF0, 0, 0, map, &cfi, cfi.device_type, NULL);
 37	cfi_send_gen_cmd(0x98, 0x55, 0, map, &cfi, cfi.device_type, NULL);
 38
 39	while (count--) {
 40		ret = cfi_qry_present(map, 0, &cfi);
 41		if (ret)
 42			pass_count++;
 43		else
 44			pass_count = 0;
 45		if (pass_count == 5)
 46			break;
 47	}
 48
 49	cfi_qry_mode_off(0, map, &cfi);
 50
 51	return ret;
 52}
 53
 54static const struct hyperbus_ops am654_hbmc_ops = {
 55	.calibrate = am654_hbmc_calibrate,
 56};
 57
 58static int am654_hbmc_probe(struct platform_device *pdev)
 59{
 60	struct device *dev = &pdev->dev;
 61	struct am654_hbmc_priv *priv;
 62	int ret;
 63
 64	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
 65	if (!priv)
 66		return -ENOMEM;
 67
 68	platform_set_drvdata(pdev, priv);
 69
 70	if (of_property_read_bool(dev->of_node, "mux-controls")) {
 71		struct mux_control *control = devm_mux_control_get(dev, NULL);
 72
 73		if (IS_ERR(control))
 74			return PTR_ERR(control);
 75
 76		ret = mux_control_select(control, 1);
 77		if (ret) {
 78			dev_err(dev, "Failed to select HBMC mux\n");
 79			return ret;
 80		}
 81		priv->mux_ctrl = control;
 82	}
 83
 84	pm_runtime_enable(dev);
 85	ret = pm_runtime_get_sync(dev);
 86	if (ret < 0) {
 87		pm_runtime_put_noidle(dev);
 88		goto disable_pm;
 89	}
 90
 91	priv->ctlr.dev = dev;
 92	priv->ctlr.ops = &am654_hbmc_ops;
 93	priv->hbdev.ctlr = &priv->ctlr;
 94	priv->hbdev.np = of_get_next_child(dev->of_node, NULL);
 95	ret = hyperbus_register_device(&priv->hbdev);
 96	if (ret) {
 97		dev_err(dev, "failed to register controller\n");
 98		pm_runtime_put_sync(&pdev->dev);
 99		goto disable_pm;
100	}
101
102	return 0;
103disable_pm:
104	pm_runtime_disable(dev);
105	if (priv->mux_ctrl)
106		mux_control_deselect(priv->mux_ctrl);
107	return ret;
108}
109
110static int am654_hbmc_remove(struct platform_device *pdev)
111{
112	struct am654_hbmc_priv *priv = platform_get_drvdata(pdev);
113	int ret;
114
115	ret = hyperbus_unregister_device(&priv->hbdev);
116	if (priv->mux_ctrl)
117		mux_control_deselect(priv->mux_ctrl);
118	pm_runtime_put_sync(&pdev->dev);
119	pm_runtime_disable(&pdev->dev);
120
121	return ret;
122}
123
124static const struct of_device_id am654_hbmc_dt_ids[] = {
125	{
126		.compatible = "ti,am654-hbmc",
127	},
128	{ /* end of table */ }
129};
130
131MODULE_DEVICE_TABLE(of, am654_hbmc_dt_ids);
132
133static struct platform_driver am654_hbmc_platform_driver = {
134	.probe = am654_hbmc_probe,
135	.remove = am654_hbmc_remove,
136	.driver = {
137		.name = "hbmc-am654",
138		.of_match_table = am654_hbmc_dt_ids,
139	},
140};
141
142module_platform_driver(am654_hbmc_platform_driver);
143
144MODULE_DESCRIPTION("HBMC driver for AM654 SoC");
145MODULE_LICENSE("GPL v2");
146MODULE_ALIAS("platform:hbmc-am654");
147MODULE_AUTHOR("Vignesh Raghavendra <vigneshr@ti.com>");