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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Copyright 2015 Toradex AG4 *5 * Stefan Agner <stefan@agner.ch>6 *7 * Freescale TCON device driver8 */9 10#include <linux/clk.h>11#include <linux/io.h>12#include <linux/mm.h>13#include <linux/of_address.h>14#include <linux/platform_device.h>15#include <linux/regmap.h>16 17#include "fsl_tcon.h"18 19void fsl_tcon_bypass_disable(struct fsl_tcon *tcon)20{21 regmap_update_bits(tcon->regs, FSL_TCON_CTRL1,22 FSL_TCON_CTRL1_TCON_BYPASS, 0);23}24 25void fsl_tcon_bypass_enable(struct fsl_tcon *tcon)26{27 regmap_update_bits(tcon->regs, FSL_TCON_CTRL1,28 FSL_TCON_CTRL1_TCON_BYPASS,29 FSL_TCON_CTRL1_TCON_BYPASS);30}31 32static struct regmap_config fsl_tcon_regmap_config = {33 .reg_bits = 32,34 .reg_stride = 4,35 .val_bits = 32,36 37 .name = "tcon",38};39 40static int fsl_tcon_init_regmap(struct device *dev,41 struct fsl_tcon *tcon,42 struct device_node *np)43{44 struct resource res;45 void __iomem *regs;46 47 if (of_address_to_resource(np, 0, &res))48 return -EINVAL;49 50 regs = devm_ioremap_resource(dev, &res);51 if (IS_ERR(regs))52 return PTR_ERR(regs);53 54 tcon->regs = devm_regmap_init_mmio(dev, regs,55 &fsl_tcon_regmap_config);56 return PTR_ERR_OR_ZERO(tcon->regs);57}58 59struct fsl_tcon *fsl_tcon_init(struct device *dev)60{61 struct fsl_tcon *tcon;62 struct device_node *np;63 int ret;64 65 /* TCON node is not mandatory, some devices do not provide TCON */66 np = of_parse_phandle(dev->of_node, "fsl,tcon", 0);67 if (!np)68 return NULL;69 70 tcon = devm_kzalloc(dev, sizeof(*tcon), GFP_KERNEL);71 if (!tcon)72 goto err_node_put;73 74 ret = fsl_tcon_init_regmap(dev, tcon, np);75 if (ret) {76 dev_err(dev, "Couldn't create the TCON regmap\n");77 goto err_node_put;78 }79 80 tcon->ipg_clk = of_clk_get_by_name(np, "ipg");81 if (IS_ERR(tcon->ipg_clk)) {82 dev_err(dev, "Couldn't get the TCON bus clock\n");83 goto err_node_put;84 }85 86 ret = clk_prepare_enable(tcon->ipg_clk);87 if (ret) {88 dev_err(dev, "Couldn't enable the TCON clock\n");89 goto err_node_put;90 }91 92 of_node_put(np);93 dev_info(dev, "Using TCON in bypass mode\n");94 95 return tcon;96 97err_node_put:98 of_node_put(np);99 return NULL;100}101 102void fsl_tcon_free(struct fsl_tcon *tcon)103{104 clk_disable_unprepare(tcon->ipg_clk);105 clk_put(tcon->ipg_clk);106}107 108