diff options
Diffstat (limited to 'sound/soc/tegra/tegra20_das.c')
| -rw-r--r-- | sound/soc/tegra/tegra20_das.c | 205 |
1 files changed, 205 insertions, 0 deletions
diff --git a/sound/soc/tegra/tegra20_das.c b/sound/soc/tegra/tegra20_das.c new file mode 100644 index 000000000..c620ab0c6 --- /dev/null +++ b/sound/soc/tegra/tegra20_das.c @@ -0,0 +1,205 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * tegra20_das.c - Tegra20 DAS driver + * + * Author: Stephen Warren <swarren@nvidia.com> + * Copyright (C) 2010 - NVIDIA, Inc. + */ + +#include <linux/device.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> +#include <linux/slab.h> +#include <sound/soc.h> + +#define DRV_NAME "tegra20-das" + +/* Register TEGRA20_DAS_DAP_CTRL_SEL */ +#define TEGRA20_DAS_DAP_CTRL_SEL 0x00 +#define TEGRA20_DAS_DAP_CTRL_SEL_COUNT 5 +#define TEGRA20_DAS_DAP_CTRL_SEL_STRIDE 4 +#define TEGRA20_DAS_DAP_CTRL_SEL_DAP_MS_SEL_P 31 +#define TEGRA20_DAS_DAP_CTRL_SEL_DAP_MS_SEL_S 1 +#define TEGRA20_DAS_DAP_CTRL_SEL_DAP_SDATA1_TX_RX_P 30 +#define TEGRA20_DAS_DAP_CTRL_SEL_DAP_SDATA1_TX_RX_S 1 +#define TEGRA20_DAS_DAP_CTRL_SEL_DAP_SDATA2_TX_RX_P 29 +#define TEGRA20_DAS_DAP_CTRL_SEL_DAP_SDATA2_TX_RX_S 1 +#define TEGRA20_DAS_DAP_CTRL_SEL_DAP_CTRL_SEL_P 0 +#define TEGRA20_DAS_DAP_CTRL_SEL_DAP_CTRL_SEL_S 5 + +/* Values for field TEGRA20_DAS_DAP_CTRL_SEL_DAP_CTRL_SEL */ +#define TEGRA20_DAS_DAP_SEL_DAC1 0 +#define TEGRA20_DAS_DAP_SEL_DAC2 1 +#define TEGRA20_DAS_DAP_SEL_DAC3 2 +#define TEGRA20_DAS_DAP_SEL_DAP1 16 +#define TEGRA20_DAS_DAP_SEL_DAP2 17 +#define TEGRA20_DAS_DAP_SEL_DAP3 18 +#define TEGRA20_DAS_DAP_SEL_DAP4 19 +#define TEGRA20_DAS_DAP_SEL_DAP5 20 + +/* Register TEGRA20_DAS_DAC_INPUT_DATA_CLK_SEL */ +#define TEGRA20_DAS_DAC_INPUT_DATA_CLK_SEL 0x40 +#define TEGRA20_DAS_DAC_INPUT_DATA_CLK_SEL_COUNT 3 +#define TEGRA20_DAS_DAC_INPUT_DATA_CLK_SEL_STRIDE 4 +#define TEGRA20_DAS_DAC_INPUT_DATA_CLK_SEL_DAC_SDATA2_SEL_P 28 +#define TEGRA20_DAS_DAC_INPUT_DATA_CLK_SEL_DAC_SDATA2_SEL_S 4 +#define TEGRA20_DAS_DAC_INPUT_DATA_CLK_SEL_DAC_SDATA1_SEL_P 24 +#define TEGRA20_DAS_DAC_INPUT_DATA_CLK_SEL_DAC_SDATA1_SEL_S 4 +#define TEGRA20_DAS_DAC_INPUT_DATA_CLK_SEL_DAC_CLK_SEL_P 0 +#define TEGRA20_DAS_DAC_INPUT_DATA_CLK_SEL_DAC_CLK_SEL_S 4 + +/* + * Values for: + * TEGRA20_DAS_DAC_INPUT_DATA_CLK_SEL_DAC_SDATA2_SEL + * TEGRA20_DAS_DAC_INPUT_DATA_CLK_SEL_DAC_SDATA1_SEL + * TEGRA20_DAS_DAC_INPUT_DATA_CLK_SEL_DAC_CLK_SEL + */ +#define TEGRA20_DAS_DAC_SEL_DAP1 0 +#define TEGRA20_DAS_DAC_SEL_DAP2 1 +#define TEGRA20_DAS_DAC_SEL_DAP3 2 +#define TEGRA20_DAS_DAC_SEL_DAP4 3 +#define TEGRA20_DAS_DAC_SEL_DAP5 4 + +/* + * Names/IDs of the DACs/DAPs. + */ + +#define TEGRA20_DAS_DAP_ID_1 0 +#define TEGRA20_DAS_DAP_ID_2 1 +#define TEGRA20_DAS_DAP_ID_3 2 +#define TEGRA20_DAS_DAP_ID_4 3 +#define TEGRA20_DAS_DAP_ID_5 4 + +#define TEGRA20_DAS_DAC_ID_1 0 +#define TEGRA20_DAS_DAC_ID_2 1 +#define TEGRA20_DAS_DAC_ID_3 2 + +struct tegra20_das { + struct regmap *regmap; +}; + +/* + * Terminology: + * DAS: Digital audio switch (HW module controlled by this driver) + * DAP: Digital audio port (port/pins on Tegra device) + * DAC: Digital audio controller (e.g. I2S or AC97 controller elsewhere) + * + * The Tegra DAS is a mux/cross-bar which can connect each DAP to a specific + * DAC, or another DAP. When DAPs are connected, one must be the master and + * one the slave. Each DAC allows selection of a specific DAP for input, to + * cater for the case where N DAPs are connected to 1 DAC for broadcast + * output. + * + * This driver is dumb; no attempt is made to ensure that a valid routing + * configuration is programmed. + */ + +static inline void tegra20_das_write(struct tegra20_das *das, u32 reg, u32 val) +{ + regmap_write(das->regmap, reg, val); +} + +static void tegra20_das_connect_dap_to_dac(struct tegra20_das *das, int dap, int dac) +{ + u32 addr; + u32 reg; + + addr = TEGRA20_DAS_DAP_CTRL_SEL + + (dap * TEGRA20_DAS_DAP_CTRL_SEL_STRIDE); + reg = dac << TEGRA20_DAS_DAP_CTRL_SEL_DAP_CTRL_SEL_P; + + tegra20_das_write(das, addr, reg); +} + +static void tegra20_das_connect_dac_to_dap(struct tegra20_das *das, int dac, int dap) +{ + u32 addr; + u32 reg; + + addr = TEGRA20_DAS_DAC_INPUT_DATA_CLK_SEL + + (dac * TEGRA20_DAS_DAC_INPUT_DATA_CLK_SEL_STRIDE); + reg = dap << TEGRA20_DAS_DAC_INPUT_DATA_CLK_SEL_DAC_CLK_SEL_P | + dap << TEGRA20_DAS_DAC_INPUT_DATA_CLK_SEL_DAC_SDATA1_SEL_P | + dap << TEGRA20_DAS_DAC_INPUT_DATA_CLK_SEL_DAC_SDATA2_SEL_P; + + tegra20_das_write(das, addr, reg); +} + +#define LAST_REG(name) \ + (TEGRA20_DAS_##name + \ + (TEGRA20_DAS_##name##_STRIDE * (TEGRA20_DAS_##name##_COUNT - 1))) + +static bool tegra20_das_wr_rd_reg(struct device *dev, unsigned int reg) +{ + if (reg <= LAST_REG(DAP_CTRL_SEL)) + return true; + if ((reg >= TEGRA20_DAS_DAC_INPUT_DATA_CLK_SEL) && + (reg <= LAST_REG(DAC_INPUT_DATA_CLK_SEL))) + return true; + + return false; +} + +static const struct regmap_config tegra20_das_regmap_config = { + .reg_bits = 32, + .reg_stride = 4, + .val_bits = 32, + .max_register = LAST_REG(DAC_INPUT_DATA_CLK_SEL), + .writeable_reg = tegra20_das_wr_rd_reg, + .readable_reg = tegra20_das_wr_rd_reg, + .cache_type = REGCACHE_FLAT, +}; + +static int tegra20_das_probe(struct platform_device *pdev) +{ + void __iomem *regs; + struct tegra20_das *das; + + das = devm_kzalloc(&pdev->dev, sizeof(struct tegra20_das), GFP_KERNEL); + if (!das) + return -ENOMEM; + + regs = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(regs)) + return PTR_ERR(regs); + + das->regmap = devm_regmap_init_mmio(&pdev->dev, regs, + &tegra20_das_regmap_config); + if (IS_ERR(das->regmap)) { + dev_err(&pdev->dev, "regmap init failed\n"); + return PTR_ERR(das->regmap); + } + + tegra20_das_connect_dap_to_dac(das, TEGRA20_DAS_DAP_ID_1, + TEGRA20_DAS_DAP_SEL_DAC1); + tegra20_das_connect_dac_to_dap(das, TEGRA20_DAS_DAC_ID_1, + TEGRA20_DAS_DAC_SEL_DAP1); + tegra20_das_connect_dap_to_dac(das, TEGRA20_DAS_DAP_ID_3, + TEGRA20_DAS_DAP_SEL_DAC3); + tegra20_das_connect_dac_to_dap(das, TEGRA20_DAS_DAC_ID_3, + TEGRA20_DAS_DAC_SEL_DAP3); + + return 0; +} + +static const struct of_device_id tegra20_das_of_match[] = { + { .compatible = "nvidia,tegra20-das", }, + {}, +}; + +static struct platform_driver tegra20_das_driver = { + .probe = tegra20_das_probe, + .driver = { + .name = DRV_NAME, + .of_match_table = tegra20_das_of_match, + }, +}; +module_platform_driver(tegra20_das_driver); + +MODULE_AUTHOR("Stephen Warren <swarren@nvidia.com>"); +MODULE_DESCRIPTION("Tegra20 DAS driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:" DRV_NAME); +MODULE_DEVICE_TABLE(of, tegra20_das_of_match); |