diff options
Diffstat (limited to 'drivers/gpu/drm/fsl-dcu/fsl_tcon.c')
| -rw-r--r-- | drivers/gpu/drm/fsl-dcu/fsl_tcon.c | 111 |
1 files changed, 111 insertions, 0 deletions
diff --git a/drivers/gpu/drm/fsl-dcu/fsl_tcon.c b/drivers/gpu/drm/fsl-dcu/fsl_tcon.c new file mode 100644 index 000000000000..bbe34f1c0505 --- /dev/null +++ b/drivers/gpu/drm/fsl-dcu/fsl_tcon.c @@ -0,0 +1,111 @@ +/* + * Copyright 2015 Toradex AG + * + * Stefan Agner <stefan@agner.ch> + * + * Freescale TCON device driver + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ + +#include <linux/clk.h> +#include <linux/io.h> +#include <linux/mm.h> +#include <linux/of_address.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> + +#include "fsl_tcon.h" + +void fsl_tcon_bypass_disable(struct fsl_tcon *tcon) +{ + regmap_update_bits(tcon->regs, FSL_TCON_CTRL1, + FSL_TCON_CTRL1_TCON_BYPASS, 0); +} + +void fsl_tcon_bypass_enable(struct fsl_tcon *tcon) +{ + regmap_update_bits(tcon->regs, FSL_TCON_CTRL1, + FSL_TCON_CTRL1_TCON_BYPASS, + FSL_TCON_CTRL1_TCON_BYPASS); +} + +static struct regmap_config fsl_tcon_regmap_config = { + .reg_bits = 32, + .reg_stride = 4, + .val_bits = 32, + + .name = "tcon", +}; + +static int fsl_tcon_init_regmap(struct device *dev, + struct fsl_tcon *tcon, + struct device_node *np) +{ + struct resource res; + void __iomem *regs; + + if (of_address_to_resource(np, 0, &res)) + return -EINVAL; + + regs = devm_ioremap_resource(dev, &res); + if (IS_ERR(regs)) + return PTR_ERR(regs); + + tcon->regs = devm_regmap_init_mmio(dev, regs, + &fsl_tcon_regmap_config); + if (IS_ERR(tcon->regs)) + return PTR_ERR(tcon->regs); + + return 0; +} + +struct fsl_tcon *fsl_tcon_init(struct device *dev) +{ + struct fsl_tcon *tcon; + struct device_node *np; + int ret; + + /* TCON node is not mandatory, some devices do not provide TCON */ + np = of_parse_phandle(dev->of_node, "fsl,tcon", 0); + if (!np) + return NULL; + + tcon = devm_kzalloc(dev, sizeof(*tcon), GFP_KERNEL); + if (!tcon) { + ret = -ENOMEM; + goto err_node_put; + } + + ret = fsl_tcon_init_regmap(dev, tcon, np); + if (ret) { + dev_err(dev, "Couldn't create the TCON regmap\n"); + goto err_node_put; + } + + tcon->ipg_clk = of_clk_get_by_name(np, "ipg"); + if (IS_ERR(tcon->ipg_clk)) { + dev_err(dev, "Couldn't get the TCON bus clock\n"); + goto err_node_put; + } + + clk_prepare_enable(tcon->ipg_clk); + + dev_info(dev, "Using TCON in bypass mode\n"); + + return tcon; + +err_node_put: + of_node_put(np); + return NULL; +} + +void fsl_tcon_free(struct fsl_tcon *tcon) +{ + clk_disable_unprepare(tcon->ipg_clk); + clk_put(tcon->ipg_clk); +} + |