package/kernel/mac80211/patches/ath9k/600-v5.16-ath9k-fetch-calibration-data-via-nvmem-subsystem.patch

   1 From dab16ef495dbb3cabb355b6c80f0771a4a25e35d Mon Sep 17 00:00:00 2001
   2 From: Christian Lamparter <chunkeey@gmail.com>
   3 Date: Fri, 20 Aug 2021 22:44:52 +0200
   4 Subject: [PATCH] ath9k: fetch calibration data via nvmem subsystem
   5
   6 On most embedded ath9k devices (like range extenders,
   7 routers, accesspoints, ...) the calibration data is
   8 stored in a MTD partitions named "ART", or "caldata"/
   9 "calibration".
  10
  11 Ever since commit
  12 4b361cfa8624 ("mtd: core: add OTP nvmem provider support")
  13 all MTD partitions are all automatically available through
  14 the nvmem subsystem. This allows drivers like ath9k to read
  15 the necessary data without needing any userspace helpers
  16 that would do this extraction.
  17
  18 Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
  19 ---
  20
  21 includes:
  22
  23 From 57671351379b2051cfb07fc14e0bead9916a0880 Mon Sep 17 00:00:00 2001
  24 From: Dan Carpenter <dan.carpenter@oracle.com>
  25 Date: Mon, 11 Oct 2021 18:18:01 +0300
  26 Subject: ath9k: fix an IS_ERR() vs NULL check
  27
  28 The devm_kmemdup() function doesn't return error pointers, it returns
  29 NULL on error.
  30
  31 Fixes: eb3a97a69be8 ("ath9k: fetch calibration data via nvmem subsystem")
  32 Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
  33 Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
  34 Link: https://lore.kernel.org/r/20211011123533.GA15188@kili
  35
  36 ---
  37
  38 --- a/drivers/net/wireless/ath/ath9k/eeprom.c
  39 +++ b/drivers/net/wireless/ath/ath9k/eeprom.c
  40 @@ -135,13 +135,23 @@ static bool ath9k_hw_nvram_read_firmware
  41                                          offset, data);
  42  }
  43
  44 +static bool ath9k_hw_nvram_read_nvmem(struct ath_hw *ah, off_t offset,
  45 +                                     u16 *data)
  46 +{
  47 +       return ath9k_hw_nvram_read_array(ah->nvmem_blob,
  48 +                                        ah->nvmem_blob_len / sizeof(u16),
  49 +                                        offset, data);
  50 +}
  51 +
  52  bool ath9k_hw_nvram_read(struct ath_hw *ah, u32 off, u16 *data)
  53  {
  54         struct ath_common *common = ath9k_hw_common(ah);
  55         struct ath9k_platform_data *pdata = ah->dev->platform_data;
  56         bool ret;
  57
  58 -       if (ah->eeprom_blob)
  59 +       if (ah->nvmem_blob)
  60 +               ret = ath9k_hw_nvram_read_nvmem(ah, off, data);
  61 +       else if (ah->eeprom_blob)
  62                 ret = ath9k_hw_nvram_read_firmware(ah->eeprom_blob, off, data);
  63         else if (pdata && !pdata->use_eeprom)
  64                 ret = ath9k_hw_nvram_read_pdata(pdata, off, data);
  65 --- a/drivers/net/wireless/ath/ath9k/hw.h
  66 +++ b/drivers/net/wireless/ath/ath9k/hw.h
  67 @@ -988,6 +988,8 @@ struct ath_hw {
  68         bool disable_5ghz;
  69
  70         const struct firmware *eeprom_blob;
  71 +       u16 *nvmem_blob;        /* devres managed */
  72 +       size_t nvmem_blob_len;
  73
  74         struct ath_dynack dynack;
  75
  76 --- a/drivers/net/wireless/ath/ath9k/init.c
  77 +++ b/drivers/net/wireless/ath/ath9k/init.c
  78 @@ -22,6 +22,7 @@
  79  #include <linux/module.h>
  80  #include <linux/of.h>
  81  #include <linux/of_net.h>
  82 +#include <linux/nvmem-consumer.h>
  83  #include <linux/relay.h>
  84  #include <linux/dmi.h>
  85  #include <net/ieee80211_radiotap.h>
  86 @@ -568,6 +569,57 @@ static void ath9k_eeprom_release(struct
  87         release_firmware(sc->sc_ah->eeprom_blob);
  88  }
  89
  90 +static int ath9k_nvmem_request_eeprom(struct ath_softc *sc)
  91 +{
  92 +       struct ath_hw *ah = sc->sc_ah;
  93 +       struct nvmem_cell *cell;
  94 +       void *buf;
  95 +       size_t len;
  96 +       int err;
  97 +
  98 +       cell = devm_nvmem_cell_get(sc->dev, "calibration");
  99 +       if (IS_ERR(cell)) {
 100 +               err = PTR_ERR(cell);
 101 +
 102 +               /* nvmem cell might not be defined, or the nvmem
 103 +                * subsystem isn't included. In this case, follow
 104 +                * the established "just return 0;" convention of
 105 +                * ath9k_init_platform to say:
 106 +                * "All good. Nothing to see here. Please go on."
 107 +                */
 108 +               if (err == -ENOENT || err == -EOPNOTSUPP)
 109 +                       return 0;
 110 +
 111 +               return err;
 112 +       }
 113 +
 114 +       buf = nvmem_cell_read(cell, &len);
 115 +       if (IS_ERR(buf))
 116 +               return PTR_ERR(buf);
 117 +
 118 +       /* run basic sanity checks on the returned nvram cell length.
 119 +        * That length has to be a multiple of a "u16" (i.e.: & 1).
 120 +        * Furthermore, it has to be more than "let's say" 512 bytes
 121 +        * but less than the maximum of AR9300_EEPROM_SIZE (16kb).
 122 +        */
 123 +       if (((len & 1) == 1) || (len < 512) || (len >= AR9300_EEPROM_SIZE)) {
 124 +               kfree(buf);
 125 +               return -EINVAL;
 126 +       }
 127 +
 128 +       /* devres manages the calibration values release on shutdown */
 129 +       ah->nvmem_blob = (u16 *)devm_kmemdup(sc->dev, buf, len, GFP_KERNEL);
 130 +       kfree(buf);
 131 +       if (!ah->nvmem_blob)
 132 +               return -ENOMEM;
 133 +
 134 +       ah->nvmem_blob_len = len;
 135 +       ah->ah_flags &= ~AH_USE_EEPROM;
 136 +       ah->ah_flags |= AH_NO_EEP_SWAP;
 137 +
 138 +       return 0;
 139 +}
 140 +
 141  static int ath9k_init_platform(struct ath_softc *sc)
 142  {
 143         struct ath9k_platform_data *pdata = sc->dev->platform_data;
 144 @@ -710,6 +762,10 @@ static int ath9k_init_softc(u16 devid, s
 145         if (ret)
 146                 return ret;
 147
 148 +       ret = ath9k_nvmem_request_eeprom(sc);
 149 +       if (ret)
 150 +               return ret;
 151 +
 152         if (ath9k_led_active_high != -1)
 153                 ah->config.led_active_high = ath9k_led_active_high == 1;
 154