sound/soc/sunxi/sun8i-adda-pr-regmap.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * This driver provides regmap to access to analog part of audio codec
   4  * found on Allwinner A23, A31s, A33, H3 and A64 Socs
   5  *
   6  * Copyright 2016 Chen-Yu Tsai <wens@csie.org>
   7  * Copyright (C) 2018 Vasily Khoruzhick <anarsoul@gmail.com>
   8  */
   9
  10 #include <linux/io.h>
  11 #include <linux/kernel.h>
  12 #include <linux/module.h>
  13 #include <linux/regmap.h>
  14
  15 #include "sun8i-adda-pr-regmap.h"
  16
  17 /* Analog control register access bits */
  18 #define ADDA_PR                 0x0             /* PRCM base + 0x1c0 */
  19 #define ADDA_PR_RESET                   BIT(28)
  20 #define ADDA_PR_WRITE                   BIT(24)
  21 #define ADDA_PR_ADDR_SHIFT              16
  22 #define ADDA_PR_ADDR_MASK               GENMASK(4, 0)
  23 #define ADDA_PR_DATA_IN_SHIFT           8
  24 #define ADDA_PR_DATA_IN_MASK            GENMASK(7, 0)
  25 #define ADDA_PR_DATA_OUT_SHIFT          0
  26 #define ADDA_PR_DATA_OUT_MASK           GENMASK(7, 0)
  27
  28 /* regmap access bits */
  29 static int adda_reg_read(void *context, unsigned int reg, unsigned int *val)
  30 {
  31         void __iomem *base = (void __iomem *)context;
  32         u32 tmp;
  33
  34         /* De-assert reset */
  35         writel(readl(base) | ADDA_PR_RESET, base);
  36
  37         /* Clear write bit */
  38         writel(readl(base) & ~ADDA_PR_WRITE, base);
  39
  40         /* Set register address */
  41         tmp = readl(base);
  42         tmp &= ~(ADDA_PR_ADDR_MASK << ADDA_PR_ADDR_SHIFT);
  43         tmp |= (reg & ADDA_PR_ADDR_MASK) << ADDA_PR_ADDR_SHIFT;
  44         writel(tmp, base);
  45
  46         /* Read back value */
  47         *val = readl(base) & ADDA_PR_DATA_OUT_MASK;
  48
  49         return 0;
  50 }
  51
  52 static int adda_reg_write(void *context, unsigned int reg, unsigned int val)
  53 {
  54         void __iomem *base = (void __iomem *)context;
  55         u32 tmp;
  56
  57         /* De-assert reset */
  58         writel(readl(base) | ADDA_PR_RESET, base);
  59
  60         /* Set register address */
  61         tmp = readl(base);
  62         tmp &= ~(ADDA_PR_ADDR_MASK << ADDA_PR_ADDR_SHIFT);
  63         tmp |= (reg & ADDA_PR_ADDR_MASK) << ADDA_PR_ADDR_SHIFT;
  64         writel(tmp, base);
  65
  66         /* Set data to write */
  67         tmp = readl(base);
  68         tmp &= ~(ADDA_PR_DATA_IN_MASK << ADDA_PR_DATA_IN_SHIFT);
  69         tmp |= (val & ADDA_PR_DATA_IN_MASK) << ADDA_PR_DATA_IN_SHIFT;
  70         writel(tmp, base);
  71
  72         /* Set write bit to signal a write */
  73         writel(readl(base) | ADDA_PR_WRITE, base);
  74
  75         /* Clear write bit */
  76         writel(readl(base) & ~ADDA_PR_WRITE, base);
  77
  78         return 0;
  79 }
  80
  81 static const struct regmap_config adda_pr_regmap_cfg = {
  82         .name           = "adda-pr",
  83         .reg_bits       = 5,
  84         .reg_stride     = 1,
  85         .val_bits       = 8,
  86         .reg_read       = adda_reg_read,
  87         .reg_write      = adda_reg_write,
  88         .fast_io        = true,
  89         .max_register   = 31,
  90 };
  91
  92 struct regmap *sun8i_adda_pr_regmap_init(struct device *dev,
  93                                          void __iomem *base)
  94 {
  95         return devm_regmap_init(dev, NULL, base, &adda_pr_regmap_cfg);
  96 }
  97 EXPORT_SYMBOL_GPL(sun8i_adda_pr_regmap_init);
  98
  99 MODULE_DESCRIPTION("Allwinner analog audio codec regmap driver");
 100 MODULE_AUTHOR("Vasily Khoruzhick <anarsoul@gmail.com>");
 101 MODULE_LICENSE("GPL");
 102 MODULE_ALIAS("platform:sunxi-adda-pr");