rtc: pcf2127: add variant-specific configuration structure

Create variant-specific configuration structures to simplify the
implementation of new variants into this driver. It will also avoid
to have too many tests for a specific variant, or a list of variants
for new devices, inside the code itself.

Add configuration options for the support of the NVMEM, bit CD0 in
register WD_CTL as well as the maximum number of registers for each
variant, instead of hardcoding the variant (PCF2127) inside the
i2c_device_id and spi_device_id structures.

Also specify a different maximum number of registers (max_register)
for the PCF2129.

Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20230622145800.2442116-6-hugo@hugovil.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

diff --git a/drivers/rtc/rtc-pcf2127.c b/drivers/rtc/rtc-pcf2127.c
index 309d1710a1c85ac86fec06ff0ae6501f14089549..23ab872c36cb2c1a93c1d12efe7657dd1d3f4a17 100644 (file)
--- a/drivers/rtc/rtc-pcf2127.c
+++ b/drivers/rtc/rtc-pcf2127.c
@@ -21,6 +21,7 @@
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/of_irq.h>
+#include <linux/of_device.h>
 #include <linux/regmap.h>
 #include <linux/watchdog.h>
 
@@ -89,10 +90,24 @@
                PCF2127_BIT_CTRL2_WDTF | \
                PCF2127_BIT_CTRL2_TSF2)
 
+enum pcf21xx_type {
+       PCF2127,
+       PCF2129,
+       PCF21XX_LAST_ID
+};
+
+struct pcf21xx_config {
+       int type; /* IC variant */
+       int max_register;
+       unsigned int has_nvmem:1;
+       unsigned int has_bit_wd_ctl_cd0:1;
+};
+
 struct pcf2127 {
        struct rtc_device *rtc;
        struct watchdog_device wdd;
        struct regmap *regmap;
+       const struct pcf21xx_config *cfg;
        time64_t ts;
        bool ts_valid;
        bool irq_enabled;
@@ -606,8 +621,23 @@ static const struct attribute_group pcf2127_attr_group = {
        .attrs  = pcf2127_attrs,
 };
 
+static struct pcf21xx_config pcf21xx_cfg[] = {
+       [PCF2127] = {
+               .type = PCF2127,
+               .max_register = 0x1d,
+               .has_nvmem = 1,
+               .has_bit_wd_ctl_cd0 = 1,
+       },
+       [PCF2129] = {
+               .type = PCF2129,
+               .max_register = 0x19,
+               .has_nvmem = 0,
+               .has_bit_wd_ctl_cd0 = 0,
+       },
+};
+
 static int pcf2127_probe(struct device *dev, struct regmap *regmap,
-                        int alarm_irq, const char *name, bool is_pcf2127)
+                        int alarm_irq, const char *name, const struct pcf21xx_config *config)
 {
        struct pcf2127 *pcf2127;
        int ret = 0;
@@ -620,6 +650,7 @@ static int pcf2127_probe(struct device *dev, struct regmap *regmap,
                return -ENOMEM;
 
        pcf2127->regmap = regmap;
+       pcf2127->cfg = config;
 
        dev_set_drvdata(dev, pcf2127);
 
@@ -663,7 +694,7 @@ static int pcf2127_probe(struct device *dev, struct regmap *regmap,
                set_bit(RTC_FEATURE_ALARM, pcf2127->rtc->features);
        }
 
-       if (is_pcf2127) {
+       if (pcf2127->cfg->has_nvmem) {
                struct nvmem_config nvmem_cfg = {
                        .priv = pcf2127,
                        .reg_read = pcf2127_nvmem_read,
@@ -709,7 +740,7 @@ static int pcf2127_probe(struct device *dev, struct regmap *regmap,
                                 PCF2127_BIT_WD_CTL_TF1 |
                                 PCF2127_BIT_WD_CTL_TF0,
                                 PCF2127_BIT_WD_CTL_CD1 |
-                                (is_pcf2127 ? PCF2127_BIT_WD_CTL_CD0 : 0) |
+                                (pcf2127->cfg->has_bit_wd_ctl_cd0 ? PCF2127_BIT_WD_CTL_CD0 : 0) |
                                 PCF2127_BIT_WD_CTL_TF1);
        if (ret) {
                dev_err(dev, "%s: watchdog config (wd_ctl) failed\n", __func__);
@@ -774,9 +805,9 @@ static int pcf2127_probe(struct device *dev, struct regmap *regmap,
 
 #ifdef CONFIG_OF
 static const struct of_device_id pcf2127_of_match[] = {
-       { .compatible = "nxp,pcf2127" },
-       { .compatible = "nxp,pcf2129" },
-       { .compatible = "nxp,pca2129" },
+       { .compatible = "nxp,pcf2127", .data = &pcf21xx_cfg[PCF2127] },
+       { .compatible = "nxp,pcf2129", .data = &pcf21xx_cfg[PCF2129] },
+       { .compatible = "nxp,pca2129", .data = &pcf21xx_cfg[PCF2129] },
        {}
 };
 MODULE_DEVICE_TABLE(of, pcf2127_of_match);
@@ -861,26 +892,40 @@ static const struct regmap_bus pcf2127_i2c_regmap = {
 static struct i2c_driver pcf2127_i2c_driver;
 
 static const struct i2c_device_id pcf2127_i2c_id[] = {
-       { "pcf2127", 1 },
-       { "pcf2129", 0 },
-       { "pca2129", 0 },
+       { "pcf2127", PCF2127 },
+       { "pcf2129", PCF2129 },
+       { "pca2129", PCF2129 },
        { }
 };
 MODULE_DEVICE_TABLE(i2c, pcf2127_i2c_id);
 
 static int pcf2127_i2c_probe(struct i2c_client *client)
 {
-       const struct i2c_device_id *id = i2c_match_id(pcf2127_i2c_id, client);
        struct regmap *regmap;
-       static const struct regmap_config config = {
+       static struct regmap_config config = {
                .reg_bits = 8,
                .val_bits = 8,
-               .max_register = 0x1d,
        };
+       const struct pcf21xx_config *variant;
 
        if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
                return -ENODEV;
 
+       if (client->dev.of_node) {
+               variant = of_device_get_match_data(&client->dev);
+               if (!variant)
+                       return -ENODEV;
+       } else {
+               enum pcf21xx_type type =
+                       i2c_match_id(pcf2127_i2c_id, client)->driver_data;
+
+               if (type >= PCF21XX_LAST_ID)
+                       return -ENODEV;
+               variant = &pcf21xx_cfg[type];
+       }
+
+       config.max_register = variant->max_register,
+
        regmap = devm_regmap_init(&client->dev, &pcf2127_i2c_regmap,
                                        &client->dev, &config);
        if (IS_ERR(regmap)) {
@@ -890,7 +935,7 @@ static int pcf2127_i2c_probe(struct i2c_client *client)
        }
 
        return pcf2127_probe(&client->dev, regmap, client->irq,
-                            pcf2127_i2c_driver.driver.name, id->driver_data);
+                            pcf2127_i2c_driver.driver.name, variant);
 }
 
 static struct i2c_driver pcf2127_i2c_driver = {
@@ -928,17 +973,32 @@ static void pcf2127_i2c_unregister_driver(void)
 #if IS_ENABLED(CONFIG_SPI_MASTER)
 
 static struct spi_driver pcf2127_spi_driver;
+static const struct spi_device_id pcf2127_spi_id[];
 
 static int pcf2127_spi_probe(struct spi_device *spi)
 {
-       static const struct regmap_config config = {
+       static struct regmap_config config = {
                .reg_bits = 8,
                .val_bits = 8,
                .read_flag_mask = 0xa0,
                .write_flag_mask = 0x20,
-               .max_register = 0x1d,
        };
        struct regmap *regmap;
+       const struct pcf21xx_config *variant;
+
+       if (spi->dev.of_node) {
+               variant = of_device_get_match_data(&spi->dev);
+               if (!variant)
+                       return -ENODEV;
+       } else {
+               enum pcf21xx_type type = spi_get_device_id(spi)->driver_data;
+
+               if (type >= PCF21XX_LAST_ID)
+                       return -ENODEV;
+               variant = &pcf21xx_cfg[type];
+       }
+
+       config.max_register = variant->max_register,
 
        regmap = devm_regmap_init_spi(spi, &config);
        if (IS_ERR(regmap)) {
@@ -949,13 +1009,13 @@ static int pcf2127_spi_probe(struct spi_device *spi)
 
        return pcf2127_probe(&spi->dev, regmap, spi->irq,
                             pcf2127_spi_driver.driver.name,
-                            spi_get_device_id(spi)->driver_data);
+                            variant);
 }
 
 static const struct spi_device_id pcf2127_spi_id[] = {
-       { "pcf2127", 1 },
-       { "pcf2129", 0 },
-       { "pca2129", 0 },
+       { "pcf2127", PCF2127 },
+       { "pcf2129", PCF2129 },
+       { "pca2129", PCF2129 },
        { }
 };
 MODULE_DEVICE_TABLE(spi, pcf2127_spi_id);