summaryrefslogtreecommitdiff
path: root/drivers/iio/adc/stm32-dfsdm-core.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2018-01-29 09:41:47 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2018-01-29 09:41:47 -0800
commit1c1f395b2873f59830979cf82324fbf00edfb80c (patch)
treee84c9b53a4d4bdb91ec9f4f5c059dc38dad21c76 /drivers/iio/adc/stm32-dfsdm-core.c
parent49f9c3552ccc30f4f98c45d94d7f9b335596913f (diff)
parent1c9609e3a8cf5997bd35205cfda1ff2218ee793b (diff)
downloadlinux-1c1f395b2873f59830979cf82324fbf00edfb80c.tar.gz
linux-1c1f395b2873f59830979cf82324fbf00edfb80c.tar.xz
Merge tag 'sound-4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
Pull sound updates from Takashi Iwai: "The major changes in the core API side in this cycle are the still on-going ASoC componentization works. Other than that, only few small changes such as 20bit PCM format support are found. Meanwhile the rest majority of changes are for ASoC drivers: - Large cleanups of some of the TI CODEC drivers - Continued work on Intel ASoC stuff for new quirks, ACPI GPIO handling, Kconfigs and lots of cleanups - Refactoring of the Freescale SSI driver, as preliminary work for the upcoming changes - Work on ST DFSDM driver, including the required IIO patches - New drivers for Allwinner A83T, Maxim MAX89373, SocioNext UiniPhier EVEA Tempo Semiconductor TSCS42xx and TI PCM816x, TAS5722 and TAS6424 devices - Removal of dead codes for SN95031 and board drivers Last but not least, a few HD-audio and USB-audio quirks are included as usual, too" * tag 'sound-4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (303 commits) ALSA: hda - Reduce the suspend time consumption for ALC256 ASoC: use seq_file to dump the contents of dai_list,platform_list and codec_list ASoC: soc-core: add missing EXPORT_SYMBOL_GPL() for snd_soc_rtdcom_lookup IIO: ADC: stm32-dfsdm: remove unused variable again ASoC: bcm2835: fix hw_params error when device is in prepared state ASoC: mxs-sgtl5000: Do not print error on probe deferral ASoC: sgtl5000: Do not print error on probe deferral ASoC: Intel: remove select on non-existing SND_SOC_INTEL_COMMON ALSA: usb-audio: Support changing input on Sound Blaster E1 ASoC: Intel: remove second duplicated assignment to pointer 'res' ALSA: hda/realtek - update ALC215 depop optimize ALSA: hda/realtek - Support headset mode for ALC215/ALC285/ALC289 ALSA: pcm: Fix trailing semicolon ASoC: add Component level .read/.write ASoC: cx20442: fix regression by adding back .read/.write ASoC: uda1380: fix regression by adding back .read/.write ASoC: tlv320dac33: fix regression by adding back .read/.write ALSA: hda - Use IS_REACHABLE() for dependency on input IIO: ADC: stm32-dfsdm: fix static check warning IIO: ADC: stm32-dfsdm: code optimization ...
Diffstat (limited to 'drivers/iio/adc/stm32-dfsdm-core.c')
-rw-r--r--drivers/iio/adc/stm32-dfsdm-core.c302
1 files changed, 302 insertions, 0 deletions
diff --git a/drivers/iio/adc/stm32-dfsdm-core.c b/drivers/iio/adc/stm32-dfsdm-core.c
new file mode 100644
index 000000000000..6290332cfd3f
--- /dev/null
+++ b/drivers/iio/adc/stm32-dfsdm-core.c
@@ -0,0 +1,302 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * This file is part the core part STM32 DFSDM driver
+ *
+ * Copyright (C) 2017, STMicroelectronics - All Rights Reserved
+ * Author(s): Arnaud Pouliquen <arnaud.pouliquen@st.com> for STMicroelectronics.
+ */
+
+#include <linux/clk.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+
+#include "stm32-dfsdm.h"
+
+struct stm32_dfsdm_dev_data {
+ unsigned int num_filters;
+ unsigned int num_channels;
+ const struct regmap_config *regmap_cfg;
+};
+
+#define STM32H7_DFSDM_NUM_FILTERS 4
+#define STM32H7_DFSDM_NUM_CHANNELS 8
+
+static bool stm32_dfsdm_volatile_reg(struct device *dev, unsigned int reg)
+{
+ if (reg < DFSDM_FILTER_BASE_ADR)
+ return false;
+
+ /*
+ * Mask is done on register to avoid to list registers of all
+ * filter instances.
+ */
+ switch (reg & DFSDM_FILTER_REG_MASK) {
+ case DFSDM_CR1(0) & DFSDM_FILTER_REG_MASK:
+ case DFSDM_ISR(0) & DFSDM_FILTER_REG_MASK:
+ case DFSDM_JDATAR(0) & DFSDM_FILTER_REG_MASK:
+ case DFSDM_RDATAR(0) & DFSDM_FILTER_REG_MASK:
+ return true;
+ }
+
+ return false;
+}
+
+static const struct regmap_config stm32h7_dfsdm_regmap_cfg = {
+ .reg_bits = 32,
+ .val_bits = 32,
+ .reg_stride = sizeof(u32),
+ .max_register = 0x2B8,
+ .volatile_reg = stm32_dfsdm_volatile_reg,
+ .fast_io = true,
+};
+
+static const struct stm32_dfsdm_dev_data stm32h7_dfsdm_data = {
+ .num_filters = STM32H7_DFSDM_NUM_FILTERS,
+ .num_channels = STM32H7_DFSDM_NUM_CHANNELS,
+ .regmap_cfg = &stm32h7_dfsdm_regmap_cfg,
+};
+
+struct dfsdm_priv {
+ struct platform_device *pdev; /* platform device */
+
+ struct stm32_dfsdm dfsdm; /* common data exported for all instances */
+
+ unsigned int spi_clk_out_div; /* SPI clkout divider value */
+ atomic_t n_active_ch; /* number of current active channels */
+
+ struct clk *clk; /* DFSDM clock */
+ struct clk *aclk; /* audio clock */
+};
+
+/**
+ * stm32_dfsdm_start_dfsdm - start global dfsdm interface.
+ *
+ * Enable interface if n_active_ch is not null.
+ * @dfsdm: Handle used to retrieve dfsdm context.
+ */
+int stm32_dfsdm_start_dfsdm(struct stm32_dfsdm *dfsdm)
+{
+ struct dfsdm_priv *priv = container_of(dfsdm, struct dfsdm_priv, dfsdm);
+ struct device *dev = &priv->pdev->dev;
+ unsigned int clk_div = priv->spi_clk_out_div;
+ int ret;
+
+ if (atomic_inc_return(&priv->n_active_ch) == 1) {
+ ret = clk_prepare_enable(priv->clk);
+ if (ret < 0) {
+ dev_err(dev, "Failed to start clock\n");
+ goto error_ret;
+ }
+ if (priv->aclk) {
+ ret = clk_prepare_enable(priv->aclk);
+ if (ret < 0) {
+ dev_err(dev, "Failed to start audio clock\n");
+ goto disable_clk;
+ }
+ }
+
+ /* Output the SPI CLKOUT (if clk_div == 0 clock if OFF) */
+ ret = regmap_update_bits(dfsdm->regmap, DFSDM_CHCFGR1(0),
+ DFSDM_CHCFGR1_CKOUTDIV_MASK,
+ DFSDM_CHCFGR1_CKOUTDIV(clk_div));
+ if (ret < 0)
+ goto disable_aclk;
+
+ /* Global enable of DFSDM interface */
+ ret = regmap_update_bits(dfsdm->regmap, DFSDM_CHCFGR1(0),
+ DFSDM_CHCFGR1_DFSDMEN_MASK,
+ DFSDM_CHCFGR1_DFSDMEN(1));
+ if (ret < 0)
+ goto disable_aclk;
+ }
+
+ dev_dbg(dev, "%s: n_active_ch %d\n", __func__,
+ atomic_read(&priv->n_active_ch));
+
+ return 0;
+
+disable_aclk:
+ clk_disable_unprepare(priv->aclk);
+disable_clk:
+ clk_disable_unprepare(priv->clk);
+
+error_ret:
+ atomic_dec(&priv->n_active_ch);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(stm32_dfsdm_start_dfsdm);
+
+/**
+ * stm32_dfsdm_stop_dfsdm - stop global DFSDM interface.
+ *
+ * Disable interface if n_active_ch is null
+ * @dfsdm: Handle used to retrieve dfsdm context.
+ */
+int stm32_dfsdm_stop_dfsdm(struct stm32_dfsdm *dfsdm)
+{
+ struct dfsdm_priv *priv = container_of(dfsdm, struct dfsdm_priv, dfsdm);
+ int ret;
+
+ if (atomic_dec_and_test(&priv->n_active_ch)) {
+ /* Global disable of DFSDM interface */
+ ret = regmap_update_bits(dfsdm->regmap, DFSDM_CHCFGR1(0),
+ DFSDM_CHCFGR1_DFSDMEN_MASK,
+ DFSDM_CHCFGR1_DFSDMEN(0));
+ if (ret < 0)
+ return ret;
+
+ /* Stop SPI CLKOUT */
+ ret = regmap_update_bits(dfsdm->regmap, DFSDM_CHCFGR1(0),
+ DFSDM_CHCFGR1_CKOUTDIV_MASK,
+ DFSDM_CHCFGR1_CKOUTDIV(0));
+ if (ret < 0)
+ return ret;
+
+ clk_disable_unprepare(priv->clk);
+ if (priv->aclk)
+ clk_disable_unprepare(priv->aclk);
+ }
+ dev_dbg(&priv->pdev->dev, "%s: n_active_ch %d\n", __func__,
+ atomic_read(&priv->n_active_ch));
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(stm32_dfsdm_stop_dfsdm);
+
+static int stm32_dfsdm_parse_of(struct platform_device *pdev,
+ struct dfsdm_priv *priv)
+{
+ struct device_node *node = pdev->dev.of_node;
+ struct resource *res;
+ unsigned long clk_freq;
+ unsigned int spi_freq, rem;
+ int ret;
+
+ if (!node)
+ return -EINVAL;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res) {
+ dev_err(&pdev->dev, "Failed to get memory resource\n");
+ return -ENODEV;
+ }
+ priv->dfsdm.phys_base = res->start;
+ priv->dfsdm.base = devm_ioremap_resource(&pdev->dev, res);
+
+ /*
+ * "dfsdm" clock is mandatory for DFSDM peripheral clocking.
+ * "dfsdm" or "audio" clocks can be used as source clock for
+ * the SPI clock out signal and internal processing, depending
+ * on use case.
+ */
+ priv->clk = devm_clk_get(&pdev->dev, "dfsdm");
+ if (IS_ERR(priv->clk)) {
+ dev_err(&pdev->dev, "No stm32_dfsdm_clk clock found\n");
+ return -EINVAL;
+ }
+
+ priv->aclk = devm_clk_get(&pdev->dev, "audio");
+ if (IS_ERR(priv->aclk))
+ priv->aclk = NULL;
+
+ if (priv->aclk)
+ clk_freq = clk_get_rate(priv->aclk);
+ else
+ clk_freq = clk_get_rate(priv->clk);
+
+ /* SPI clock out frequency */
+ ret = of_property_read_u32(pdev->dev.of_node, "spi-max-frequency",
+ &spi_freq);
+ if (ret < 0) {
+ /* No SPI master mode */
+ return 0;
+ }
+
+ priv->spi_clk_out_div = div_u64_rem(clk_freq, spi_freq, &rem) - 1;
+ priv->dfsdm.spi_master_freq = spi_freq;
+
+ if (rem) {
+ dev_warn(&pdev->dev, "SPI clock not accurate\n");
+ dev_warn(&pdev->dev, "%ld = %d * %d + %d\n",
+ clk_freq, spi_freq, priv->spi_clk_out_div + 1, rem);
+ }
+
+ return 0;
+};
+
+static const struct of_device_id stm32_dfsdm_of_match[] = {
+ {
+ .compatible = "st,stm32h7-dfsdm",
+ .data = &stm32h7_dfsdm_data,
+ },
+ {}
+};
+MODULE_DEVICE_TABLE(of, stm32_dfsdm_of_match);
+
+static int stm32_dfsdm_probe(struct platform_device *pdev)
+{
+ struct dfsdm_priv *priv;
+ const struct stm32_dfsdm_dev_data *dev_data;
+ struct stm32_dfsdm *dfsdm;
+ int ret;
+
+ priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->pdev = pdev;
+
+ dev_data = of_device_get_match_data(&pdev->dev);
+
+ dfsdm = &priv->dfsdm;
+ dfsdm->fl_list = devm_kcalloc(&pdev->dev, dev_data->num_filters,
+ sizeof(*dfsdm->fl_list), GFP_KERNEL);
+ if (!dfsdm->fl_list)
+ return -ENOMEM;
+
+ dfsdm->num_fls = dev_data->num_filters;
+ dfsdm->ch_list = devm_kcalloc(&pdev->dev, dev_data->num_channels,
+ sizeof(*dfsdm->ch_list),
+ GFP_KERNEL);
+ if (!dfsdm->ch_list)
+ return -ENOMEM;
+ dfsdm->num_chs = dev_data->num_channels;
+
+ ret = stm32_dfsdm_parse_of(pdev, priv);
+ if (ret < 0)
+ return ret;
+
+ dfsdm->regmap = devm_regmap_init_mmio_clk(&pdev->dev, "dfsdm",
+ dfsdm->base,
+ &stm32h7_dfsdm_regmap_cfg);
+ if (IS_ERR(dfsdm->regmap)) {
+ ret = PTR_ERR(dfsdm->regmap);
+ dev_err(&pdev->dev, "%s: Failed to allocate regmap: %d\n",
+ __func__, ret);
+ return ret;
+ }
+
+ platform_set_drvdata(pdev, dfsdm);
+
+ return devm_of_platform_populate(&pdev->dev);
+}
+
+static struct platform_driver stm32_dfsdm_driver = {
+ .probe = stm32_dfsdm_probe,
+ .driver = {
+ .name = "stm32-dfsdm",
+ .of_match_table = stm32_dfsdm_of_match,
+ },
+};
+
+module_platform_driver(stm32_dfsdm_driver);
+
+MODULE_AUTHOR("Arnaud Pouliquen <arnaud.pouliquen@st.com>");
+MODULE_DESCRIPTION("STMicroelectronics STM32 dfsdm driver");
+MODULE_LICENSE("GPL v2");