LXR linux/drivers/clk/sunxi-ng/ccu_mmc

   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Copyright (c) 2017 Chen-Yu Tsai. All rights reserved.
   4 */
   5
   6#include <linux/clk-provider.h>
   7#include <linux/clk/sunxi-ng.h>
   8#include <linux/io.h>
   9
  10#include "ccu_common.h"
  11
  12/**
  13 * sunxi_ccu_set_mmc_timing_mode: Configure the MMC clock timing mode
  14 * @clk: clock to be configured
  15 * @new_mode: true for new timing mode introduced in A83T and later
  16 *
  17 * Returns 0 on success, -ENOTSUPP if the clock does not support
  18 * switching modes.
  19 */
  20int sunxi_ccu_set_mmc_timing_mode(struct clk *clk, bool new_mode)
  21{
  22        struct clk_hw *hw = __clk_get_hw(clk);
  23        struct ccu_common *cm = hw_to_ccu_common(hw);
  24        unsigned long flags;
  25        u32 val;
  26
  27        if (!(cm->features & CCU_FEATURE_MMC_TIMING_SWITCH))
  28                return -ENOTSUPP;
  29
  30        spin_lock_irqsave(cm->lock, flags);
  31
  32        val = readl(cm->base + cm->reg);
  33        if (new_mode)
  34                val |= CCU_MMC_NEW_TIMING_MODE;
  35        else
  36                val &= ~CCU_MMC_NEW_TIMING_MODE;
  37        writel(val, cm->base + cm->reg);
  38
  39        spin_unlock_irqrestore(cm->lock, flags);
  40
  41        return 0;
  42}
  43EXPORT_SYMBOL_GPL(sunxi_ccu_set_mmc_timing_mode);
  44
  45/**
  46 * sunxi_ccu_set_mmc_timing_mode: Get the current MMC clock timing mode
  47 * @clk: clock to query
  48 *
  49 * Returns 0 if the clock is in old timing mode, > 0 if it is in
  50 * new timing mode, and -ENOTSUPP if the clock does not support
  51 * this function.
  52 */
  53int sunxi_ccu_get_mmc_timing_mode(struct clk *clk)
  54{
  55        struct clk_hw *hw = __clk_get_hw(clk);
  56        struct ccu_common *cm = hw_to_ccu_common(hw);
  57
  58        if (!(cm->features & CCU_FEATURE_MMC_TIMING_SWITCH))
  59                return -ENOTSUPP;
  60
  61        return !!(readl(cm->base + cm->reg) & CCU_MMC_NEW_TIMING_MODE);
  62}
  63EXPORT_SYMBOL_GPL(sunxi_ccu_get_mmc_timing_mode);
  64