drivers/mtd/hyperbus/hbmc-am654.c

   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/of_address.h>
  15 #include <linux/platform_device.h>
  16 #include <linux/pm_runtime.h>
  17 #include <linux/types.h>
  18
  19 #define AM654_HBMC_CALIB_COUNT 25
  20
  21 struct am654_hbmc_priv {
  22         struct hyperbus_ctlr ctlr;
  23         struct hyperbus_device hbdev;
  24         struct mux_control *mux_ctrl;
  25 };
  26
  27 static int am654_hbmc_calibrate(struct hyperbus_device *hbdev)
  28 {
  29         struct map_info *map = &hbdev->map;
  30         struct cfi_private cfi;
  31         int count = AM654_HBMC_CALIB_COUNT;
  32         int pass_count = 0;
  33         int ret;
  34
  35         cfi.interleave = 1;
  36         cfi.device_type = CFI_DEVICETYPE_X16;
  37         cfi_send_gen_cmd(0xF0, 0, 0, map, &cfi, cfi.device_type, NULL);
  38         cfi_send_gen_cmd(0x98, 0x55, 0, map, &cfi, cfi.device_type, NULL);
  39
  40         while (count--) {
  41                 ret = cfi_qry_present(map, 0, &cfi);
  42                 if (ret)
  43                         pass_count++;
  44                 else
  45                         pass_count = 0;
  46                 if (pass_count == 5)
  47                         break;
  48         }
  49
  50         cfi_qry_mode_off(0, map, &cfi);
  51
  52         return ret;
  53 }
  54
  55 static const struct hyperbus_ops am654_hbmc_ops = {
  56         .calibrate = am654_hbmc_calibrate,
  57 };
  58
  59 static int am654_hbmc_probe(struct platform_device *pdev)
  60 {
  61         struct device_node *np = pdev->dev.of_node;
  62         struct device *dev = &pdev->dev;
  63         struct am654_hbmc_priv *priv;
  64         struct resource res;
  65         int ret;
  66
  67         priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
  68         if (!priv)
  69                 return -ENOMEM;
  70
  71         platform_set_drvdata(pdev, priv);
  72
  73         ret = of_address_to_resource(np, 0, &res);
  74         if (ret)
  75                 return ret;
  76
  77         if (of_property_read_bool(dev->of_node, "mux-controls")) {
  78                 struct mux_control *control = devm_mux_control_get(dev, NULL);
  79
  80                 if (IS_ERR(control))
  81                         return PTR_ERR(control);
  82
  83                 ret = mux_control_select(control, 1);
  84                 if (ret) {
  85                         dev_err(dev, "Failed to select HBMC mux\n");
  86                         return ret;
  87                 }
  88                 priv->mux_ctrl = control;
  89         }
  90
  91         pm_runtime_enable(dev);
  92         ret = pm_runtime_get_sync(dev);
  93         if (ret < 0) {
  94                 pm_runtime_put_noidle(dev);
  95                 goto disable_pm;
  96         }
  97
  98         priv->hbdev.map.size = resource_size(&res);
  99         priv->hbdev.map.virt = devm_ioremap_resource(dev, &res);
 100         if (IS_ERR(priv->hbdev.map.virt))
 101                 return PTR_ERR(priv->hbdev.map.virt);
 102
 103         priv->ctlr.dev = dev;
 104         priv->ctlr.ops = &am654_hbmc_ops;
 105         priv->hbdev.ctlr = &priv->ctlr;
 106         priv->hbdev.np = of_get_next_child(dev->of_node, NULL);
 107         ret = hyperbus_register_device(&priv->hbdev);
 108         if (ret) {
 109                 dev_err(dev, "failed to register controller\n");
 110                 pm_runtime_put_sync(&pdev->dev);
 111                 goto disable_pm;
 112         }
 113
 114         return 0;
 115 disable_pm:
 116         pm_runtime_disable(dev);
 117         if (priv->mux_ctrl)
 118                 mux_control_deselect(priv->mux_ctrl);
 119         return ret;
 120 }
 121
 122 static int am654_hbmc_remove(struct platform_device *pdev)
 123 {
 124         struct am654_hbmc_priv *priv = platform_get_drvdata(pdev);
 125         int ret;
 126
 127         ret = hyperbus_unregister_device(&priv->hbdev);
 128         if (priv->mux_ctrl)
 129                 mux_control_deselect(priv->mux_ctrl);
 130         pm_runtime_put_sync(&pdev->dev);
 131         pm_runtime_disable(&pdev->dev);
 132
 133         return ret;
 134 }
 135
 136 static const struct of_device_id am654_hbmc_dt_ids[] = {
 137         {
 138                 .compatible = "ti,am654-hbmc",
 139         },
 140         { /* end of table */ }
 141 };
 142
 143 MODULE_DEVICE_TABLE(of, am654_hbmc_dt_ids);
 144
 145 static struct platform_driver am654_hbmc_platform_driver = {
 146         .probe = am654_hbmc_probe,
 147         .remove = am654_hbmc_remove,
 148         .driver = {
 149                 .name = "hbmc-am654",
 150                 .of_match_table = am654_hbmc_dt_ids,
 151         },
 152 };
 153
 154 module_platform_driver(am654_hbmc_platform_driver);
 155
 156 MODULE_DESCRIPTION("HBMC driver for AM654 SoC");
 157 MODULE_LICENSE("GPL v2");
 158 MODULE_ALIAS("platform:hbmc-am654");
 159 MODULE_AUTHOR("Vignesh Raghavendra <vigneshr@ti.com>");