2023-05-12 12:36:06

by Charles Keepax

[permalink] [raw]
Subject: [PATCH 09/10] spi: cs42l43: Add SPI controller support

From: Lucas Tanure <[email protected]>

The CS42L43 is an audio CODEC with integrated MIPI SoundWire interface
(Version 1.2.1 compliant), I2C, SPI, and I2S/TDM interfaces designed
for portable applications. It provides a high dynamic range, stereo
DAC for headphone output, two integrated Class D amplifiers for
loudspeakers, and two ADCs for wired headset microphone input or
stereo line input. PDM inputs are provided for digital microphones.

The SPI component incorporates a SPI controller interface for
communication with other peripheral components.

Signed-off-by: Lucas Tanure <[email protected]>
Signed-off-by: Maciej Strozek <[email protected]>
Signed-off-by: Charles Keepax <[email protected]>
---
MAINTAINERS | 1 +
drivers/spi/Kconfig | 7 +
drivers/spi/Makefile | 1 +
drivers/spi/spi-cs42l43.c | 287 ++++++++++++++++++++++++++++++++++++++
4 files changed, 296 insertions(+)
create mode 100644 drivers/spi/spi-cs42l43.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 2890f54f70afc..ca4aa5cc43b7d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4931,6 +4931,7 @@ F: Documentation/devicetree/bindings/sound/cirrus,cs*
F: drivers/irqchip/irq-cs42l43*
F: drivers/mfd/cs42l43*
F: drivers/pinctrl/cirrus/pinctrl-cs42l43*
+F: drivers/spi/spi-cs42l43*
F: include/dt-bindings/sound/cs*
F: include/linux/irqchip/cs42l43*
F: include/linux/mfd/cs42l43*
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index 3de2ebe8294aa..f6ce06de41051 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -281,6 +281,13 @@ config SPI_COLDFIRE_QSPI
This enables support for the Coldfire QSPI controller in master
mode.

+config SPI_CS42L43
+ tristate "Cirrus Logic CS42L43 SPI controller"
+ depends on MFD_CS42L43 && PINCTRL_CS42L43
+ help
+ This enables support for the SPI controller inside the Cirrus Logic
+ CS42L43 audio codec.
+
config SPI_DAVINCI
tristate "Texas Instruments DaVinci/DA8x/OMAP-L/AM1x SoC SPI controller"
depends on ARCH_DAVINCI || ARCH_KEYSTONE || COMPILE_TEST
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index 28c4817a8a74a..49937ea0d73d0 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -40,6 +40,7 @@ obj-$(CONFIG_SPI_CADENCE_QUADSPI) += spi-cadence-quadspi.o
obj-$(CONFIG_SPI_CADENCE_XSPI) += spi-cadence-xspi.o
obj-$(CONFIG_SPI_CLPS711X) += spi-clps711x.o
obj-$(CONFIG_SPI_COLDFIRE_QSPI) += spi-coldfire-qspi.o
+obj-$(CONFIG_SPI_CS42L43) += spi-cs42l43.o
obj-$(CONFIG_SPI_DAVINCI) += spi-davinci.o
obj-$(CONFIG_SPI_DLN2) += spi-dln2.o
obj-$(CONFIG_SPI_DESIGNWARE) += spi-dw.o
diff --git a/drivers/spi/spi-cs42l43.c b/drivers/spi/spi-cs42l43.c
new file mode 100644
index 0000000000000..f48999e1a74d9
--- /dev/null
+++ b/drivers/spi/spi-cs42l43.c
@@ -0,0 +1,287 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// CS42L43 SPI Controller Driver
+//
+// Copyright (C) 2022-2023 Cirrus Logic, Inc. and
+// Cirrus Logic International Semiconductor Ltd.
+
+#include <linux/device.h>
+#include <linux/errno.h>
+#include <linux/mfd/cs42l43.h>
+#include <linux/mfd/cs42l43-regs.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/regmap.h>
+#include <linux/spi/spi.h>
+
+#define CS42L43_FIFO_SIZE 16
+#define CS42L43_SPI_ROOT_HZ 40000000
+#define CS42L43_SPI_MAX_LENGTH 65532
+
+enum cs42l43_spi_cmd {
+ CS42L43_WRITE,
+ CS42L43_READ
+};
+
+struct cs42l43_spi {
+ struct device *dev;
+ struct regmap *regmap;
+ struct spi_controller *ctlr;
+};
+
+static unsigned int cs42l43_clock_divs[16] = {
+ 2, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30
+};
+
+static int cs42l43_spi_tx(struct regmap *regmap, const u8 *buf, unsigned int len)
+{
+ const u8 *end = buf + len;
+ u32 val;
+ int ret;
+
+ while (buf < end) {
+ const u8 *block = min_t(const u8 *, buf + CS42L43_FIFO_SIZE, end);
+
+ for (; buf < block - (sizeof(u32) - 1); buf += sizeof(u32))
+ regmap_write(regmap, CS42L43_TX_DATA, *(const u32 *)buf);
+
+ if (buf < block) {
+ unsigned int residue = end - buf;
+
+ memcpy(&val, buf, residue);
+ regmap_write(regmap, CS42L43_TX_DATA, val);
+ buf += residue;
+ }
+
+ regmap_write(regmap, CS42L43_TRAN_CONFIG8, CS42L43_SPI_TX_DONE_MASK);
+
+ ret = regmap_read_poll_timeout(regmap, CS42L43_TRAN_STATUS1,
+ val, (val & CS42L43_SPI_TX_REQUEST_MASK),
+ 1000, 5000);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
+static int cs42l43_spi_rx(struct regmap *regmap, u8 *buf, unsigned int len)
+{
+ const u8 *end = buf + len;
+ u32 val;
+ int ret;
+
+ while (buf < end) {
+ const u8 *block = min_t(const u8 *, buf + CS42L43_FIFO_SIZE, end);
+
+ ret = regmap_read_poll_timeout(regmap, CS42L43_TRAN_STATUS1,
+ val, (val & CS42L43_SPI_RX_REQUEST_MASK),
+ 1000, 5000);
+ if (ret)
+ return ret;
+
+ for (; buf < block - (sizeof(u32) - 1); buf += sizeof(u32)) {
+ ret = regmap_read(regmap, CS42L43_RX_DATA, (u32 *)buf);
+ if (ret)
+ return ret;
+ }
+
+ if (buf < block) {
+ unsigned int residue = end - buf;
+
+ ret = regmap_read(regmap, CS42L43_RX_DATA, &val);
+ if (ret)
+ return ret;
+
+ memcpy(buf, &val, residue);
+ buf += residue;
+ }
+
+ regmap_write(regmap, CS42L43_TRAN_CONFIG8, CS42L43_SPI_RX_DONE_MASK);
+ }
+
+ return 0;
+}
+
+static int cs42l43_transfer_one(struct spi_controller *ctlr, struct spi_device *spi,
+ struct spi_transfer *tfr)
+{
+ struct cs42l43_spi *priv = spi_controller_get_devdata(spi->controller);
+ int i, ret = -EINVAL;
+
+ for (i = 0; i < ARRAY_SIZE(cs42l43_clock_divs); i++) {
+ if (CS42L43_SPI_ROOT_HZ / cs42l43_clock_divs[i] <= tfr->speed_hz)
+ break;
+ }
+
+ if (i == ARRAY_SIZE(cs42l43_clock_divs))
+ return -EINVAL;
+
+ regmap_write(priv->regmap, CS42L43_SPI_CLK_CONFIG1, i);
+
+ if (tfr->tx_buf) {
+ regmap_write(priv->regmap, CS42L43_TRAN_CONFIG3, CS42L43_WRITE);
+ regmap_write(priv->regmap, CS42L43_TRAN_CONFIG4, tfr->len - 1);
+ } else if (tfr->rx_buf) {
+ regmap_write(priv->regmap, CS42L43_TRAN_CONFIG3, CS42L43_READ);
+ regmap_write(priv->regmap, CS42L43_TRAN_CONFIG5, tfr->len - 1);
+ }
+
+ regmap_write(priv->regmap, CS42L43_TRAN_CONFIG1, CS42L43_SPI_START_MASK);
+
+ if (tfr->tx_buf)
+ ret = cs42l43_spi_tx(priv->regmap, (const u8 *)tfr->tx_buf, tfr->len);
+ else if (tfr->rx_buf)
+ ret = cs42l43_spi_rx(priv->regmap, (u8 *)tfr->rx_buf, tfr->len);
+
+ return ret;
+}
+
+static void cs42l43_set_cs(struct spi_device *spi, bool is_high)
+{
+ struct cs42l43_spi *priv = spi_controller_get_devdata(spi->controller);
+
+ if (spi->chip_select == 0)
+ regmap_write(priv->regmap, CS42L43_SPI_CONFIG2, !is_high);
+}
+
+static int cs42l43_prepare_message(struct spi_controller *ctlr, struct spi_message *msg)
+{
+ struct cs42l43_spi *priv = spi_controller_get_devdata(ctlr);
+ struct spi_device *spi = msg->spi;
+ unsigned int spi_config1 = 0;
+
+ /* select another internal CS, which doesn't exist, so CS 0 is not used */
+ if (spi->cs_gpiod)
+ spi_config1 |= 1 << CS42L43_SPI_SS_SEL_SHIFT;
+ if (spi->mode & SPI_CPOL)
+ spi_config1 |= CS42L43_SPI_CPOL_MASK;
+ if (spi->mode & SPI_CPHA)
+ spi_config1 |= CS42L43_SPI_CPHA_MASK;
+ if (spi->mode & SPI_3WIRE)
+ spi_config1 |= CS42L43_SPI_THREE_WIRE_MASK;
+
+ regmap_write(priv->regmap, CS42L43_SPI_CONFIG1, spi_config1);
+
+ return 0;
+}
+
+static int cs42l43_prepare_transfer_hardware(struct spi_controller *ctlr)
+{
+ struct cs42l43_spi *priv = spi_controller_get_devdata(ctlr);
+ int ret;
+
+ ret = regmap_write(priv->regmap, CS42L43_BLOCK_EN2, CS42L43_SPI_MSTR_EN_MASK);
+ if (ret) {
+ dev_err(priv->dev, "Failed to enable SPI controller: %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int cs42l43_unprepare_transfer_hardware(struct spi_controller *ctlr)
+{
+ struct cs42l43_spi *priv = spi_controller_get_devdata(ctlr);
+ int ret;
+
+ ret = regmap_write(priv->regmap, CS42L43_BLOCK_EN2, 0);
+ if (ret) {
+ dev_err(priv->dev, "Failed to disable SPI controller: %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static size_t cs42l43_spi_max_length(struct spi_device *spi)
+{
+ return CS42L43_SPI_MAX_LENGTH;
+}
+
+static int cs42l43_spi_probe(struct platform_device *pdev)
+{
+ struct cs42l43 *cs42l43 = dev_get_drvdata(pdev->dev.parent);
+ struct cs42l43_spi *priv;
+ int ret;
+
+ priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->ctlr = devm_spi_alloc_master(&pdev->dev, sizeof(*priv->ctlr));
+ if (!priv->ctlr)
+ return -ENOMEM;
+
+ spi_controller_set_devdata(priv->ctlr, priv);
+
+ priv->dev = &pdev->dev;
+ priv->regmap = cs42l43->regmap;
+
+ priv->ctlr->prepare_message = cs42l43_prepare_message;
+ priv->ctlr->prepare_transfer_hardware = cs42l43_prepare_transfer_hardware;
+ priv->ctlr->unprepare_transfer_hardware = cs42l43_unprepare_transfer_hardware;
+ priv->ctlr->transfer_one = cs42l43_transfer_one;
+ priv->ctlr->set_cs = cs42l43_set_cs;
+ priv->ctlr->max_transfer_size = cs42l43_spi_max_length;
+
+ if (is_of_node(dev_fwnode(cs42l43->dev))) {
+ priv->ctlr->dev.fwnode =
+ fwnode_get_named_child_node(dev_fwnode(cs42l43->dev), "spi");
+ priv->ctlr->dev.of_node = to_of_node(dev_fwnode(&priv->ctlr->dev));
+ } else {
+ priv->ctlr->dev.fwnode = dev_fwnode(priv->dev);
+ }
+
+ priv->ctlr->mode_bits = SPI_3WIRE | SPI_CPHA | SPI_CPOL;
+ priv->ctlr->flags = SPI_CONTROLLER_HALF_DUPLEX;
+ priv->ctlr->bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(16) |
+ SPI_BPW_MASK(32);
+ priv->ctlr->min_speed_hz = CS42L43_SPI_ROOT_HZ /
+ cs42l43_clock_divs[ARRAY_SIZE(cs42l43_clock_divs) - 1];
+ priv->ctlr->max_speed_hz = CS42L43_SPI_ROOT_HZ / cs42l43_clock_divs[0];
+ priv->ctlr->use_gpio_descriptors = true;
+ priv->ctlr->auto_runtime_pm = true;
+
+ pm_runtime_enable(priv->dev);
+ pm_runtime_idle(priv->dev);
+
+ regmap_write(priv->regmap, CS42L43_TRAN_CONFIG6, CS42L43_FIFO_SIZE - 1);
+ regmap_write(priv->regmap, CS42L43_TRAN_CONFIG7, CS42L43_FIFO_SIZE - 1);
+
+ // Disable Watchdog timer and enable stall
+ regmap_write(priv->regmap, CS42L43_SPI_CONFIG3, 0);
+ regmap_write(priv->regmap, CS42L43_SPI_CONFIG4, CS42L43_SPI_STALL_ENA_MASK);
+
+ ret = devm_spi_register_controller(priv->dev, priv->ctlr);
+ if (ret) {
+ pm_runtime_disable(priv->dev);
+ dev_err(priv->dev, "Failed to register SPI controller: %d\n", ret);
+ }
+
+ return ret;
+}
+
+static int cs42l43_spi_remove(struct platform_device *pdev)
+{
+ pm_runtime_disable(&pdev->dev);
+
+ return 0;
+}
+
+static struct platform_driver cs42l43_spi_driver = {
+ .driver = {
+ .name = "cs42l43-spi",
+ },
+
+ .probe = cs42l43_spi_probe,
+ .remove = cs42l43_spi_remove,
+};
+module_platform_driver(cs42l43_spi_driver);
+
+MODULE_DESCRIPTION("CS42L43 SPI Driver");
+MODULE_AUTHOR("Lucas Tanure <[email protected]>");
+MODULE_AUTHOR("Maciej Strozek <[email protected]>");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:cs42l43-spi");
--
2.30.2



2023-05-12 19:24:18

by Andy Shevchenko

[permalink] [raw]
Subject: Re: [PATCH 09/10] spi: cs42l43: Add SPI controller support

Fri, May 12, 2023 at 01:28:37PM +0100, Charles Keepax kirjoitti:
> From: Lucas Tanure <[email protected]>
>
> The CS42L43 is an audio CODEC with integrated MIPI SoundWire interface
> (Version 1.2.1 compliant), I2C, SPI, and I2S/TDM interfaces designed
> for portable applications. It provides a high dynamic range, stereo
> DAC for headphone output, two integrated Class D amplifiers for
> loudspeakers, and two ADCs for wired headset microphone input or
> stereo line input. PDM inputs are provided for digital microphones.
>
> The SPI component incorporates a SPI controller interface for
> communication with other peripheral components.

...

> +#define CS42L43_SPI_ROOT_HZ 40000000

HZ_PER_MHZ?

...

> + const u8 *block = min_t(const u8 *, buf + CS42L43_FIFO_SIZE, end);

Wouldn't min() work?

...

> + for (; buf < block - (sizeof(u32) - 1); buf += sizeof(u32))
> + regmap_write(regmap, CS42L43_TX_DATA, *(const u32 *)buf);

This casting might be potentially wrong taking alignment into consideration.
Perhaps you need get_unaligned(). Also here the return value isn't checked,
while in the read it is.

...

> + const u8 *block = min_t(const u8 *, buf + CS42L43_FIFO_SIZE, end);

min() ?

...

> + for (; buf < block - (sizeof(u32) - 1); buf += sizeof(u32)) {
> + ret = regmap_read(regmap, CS42L43_RX_DATA, (u32 *)buf);

put_unaligned() ?

> + if (ret)
> + return ret;
> + }

...

> +static int cs42l43_prepare_transfer_hardware(struct spi_controller *ctlr)
> +{
> + struct cs42l43_spi *priv = spi_controller_get_devdata(ctlr);
> + int ret;
> +
> + ret = regmap_write(priv->regmap, CS42L43_BLOCK_EN2, CS42L43_SPI_MSTR_EN_MASK);
> + if (ret) {
> + dev_err(priv->dev, "Failed to enable SPI controller: %d\n", ret);

> + return ret;
> + }
> +
> + return 0;

return ret; ?

> +}
> +
> +static int cs42l43_unprepare_transfer_hardware(struct spi_controller *ctlr)
> +{
> + struct cs42l43_spi *priv = spi_controller_get_devdata(ctlr);
> + int ret;
> +
> + ret = regmap_write(priv->regmap, CS42L43_BLOCK_EN2, 0);
> + if (ret) {
> + dev_err(priv->dev, "Failed to disable SPI controller: %d\n", ret);
> + return ret;
> + }
> +
> + return 0;

Ditto.

> +}

...

> + if (is_of_node(dev_fwnode(cs42l43->dev))) {
> + priv->ctlr->dev.fwnode =
> + fwnode_get_named_child_node(dev_fwnode(cs42l43->dev), "spi");
> + priv->ctlr->dev.of_node = to_of_node(dev_fwnode(&priv->ctlr->dev));
> + } else {
> + priv->ctlr->dev.fwnode = dev_fwnode(priv->dev);
> + }

Can you use device_set_node() once you have an fwnode that needs to be passed?

...

> + priv->ctlr->mode_bits = SPI_3WIRE | SPI_CPHA | SPI_CPOL;

SPI_MODE_X_MASK

...

> +static struct platform_driver cs42l43_spi_driver = {
> + .driver = {
> + .name = "cs42l43-spi",
> + },

> +

Unneeded blank line.

> + .probe = cs42l43_spi_probe,
> + .remove = cs42l43_spi_remove,
> +};

--
With Best Regards,
Andy Shevchenko