linux/sound/soc/tegra/tegra20_das.c
Uwe Kleine-König fb617612fd
ASoC: tegra: tegra20_das: Drop write-only driver data member
The dev member of struct tegra20_das is only written once in .probe().
There is no loss of functionality if the member and the assignment go away.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20220629194224.175607-5-u.kleine-koenig@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>
2022-07-05 19:54:00 +01:00

206 lines
6.0 KiB
C

// 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);