mfd: si476x: Add chip properties handling code

This patch adds code related to manipulation of the properties of
SI476X chips.

Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

1 files changed, 241 insertions, 0 deletions

diff --git a/drivers/mfd/si476x-prop.c b/drivers/mfd/si476x-prop.c
new file mode 100644
index 000000000000..cfeffa6e15d9
--- /dev/null
+++ b/drivers/mfd/si476x-prop.c
@@ -0,0 +1,241 @@
+/*
+ * drivers/mfd/si476x-prop.c -- Subroutines to access
+ * properties of si476x chips
+ *
+ * Copyright (C) 2012 Innovative Converged Devices(ICD)
+ * Copyright (C) 2013 Andrey Smirnov
+ *
+ * Author: Andrey Smirnov <andrew.smirnov@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ */
+#include <linux/module.h>
+
+#include <linux/mfd/si476x-core.h>
+
+struct si476x_property_range {
+        u16 low, high;
+};
+
+static bool si476x_core_element_is_in_array(u16 element,
+                                            const u16 array[],
+                                            size_t size)
+{
+        int i;
+
+        for (i = 0; i < size; i++)
+                if (element == array[i])
+                        return true;
+
+        return false;
+}
+
+static bool si476x_core_element_is_in_range(u16 element,
+                                            const struct si476x_property_range range[],
+                                            size_t size)
+{
+        int i;
+
+        for (i = 0; i < size; i++)
+                if (element <= range[i].high && element >= range[i].low)
+                        return true;
+
+        return false;
+}
+
+static bool si476x_core_is_valid_property_a10(struct si476x_core *core,
+                                              u16 property)
+{
+        static const u16 valid_properties[] = {
+                0x0000,
+                0x0500, 0x0501,
+                0x0600,
+                0x0709, 0x070C, 0x070D, 0x70E, 0x710,
+                0x0718,
+                0x1207, 0x1208,
+                0x2007,
+                0x2300,
+        };
+
+        static const struct si476x_property_range valid_ranges[] = {
+                { 0x0200, 0x0203 },
+                { 0x0300, 0x0303 },
+                { 0x0400, 0x0404 },
+                { 0x0700, 0x0707 },
+                { 0x1100, 0x1102 },
+                { 0x1200, 0x1204 },
+                { 0x1300, 0x1306 },
+                { 0x2000, 0x2005 },
+                { 0x2100, 0x2104 },
+                { 0x2106, 0x2106 },
+                { 0x2200, 0x220E },
+                { 0x3100, 0x3104 },
+                { 0x3207, 0x320F },
+                { 0x3300, 0x3304 },
+                { 0x3500, 0x3517 },
+                { 0x3600, 0x3617 },
+                { 0x3700, 0x3717 },
+                { 0x4000, 0x4003 },
+        };
+
+        return  si476x_core_element_is_in_range(property, valid_ranges,
+                                                ARRAY_SIZE(valid_ranges)) ||
+                si476x_core_element_is_in_array(property, valid_properties,
+                                                ARRAY_SIZE(valid_properties));
+}
+
+static bool si476x_core_is_valid_property_a20(struct si476x_core *core,
+                                              u16 property)
+{
+        static const u16 valid_properties[] = {
+                0x071B,
+                0x1006,
+                0x2210,
+                0x3401,
+        };
+
+        static const struct si476x_property_range valid_ranges[] = {
+                { 0x2215, 0x2219 },
+        };
+
+        return  si476x_core_is_valid_property_a10(core, property) ||
+                si476x_core_element_is_in_range(property, valid_ranges,
+                                                ARRAY_SIZE(valid_ranges))  ||
+                si476x_core_element_is_in_array(property, valid_properties,
+                                                ARRAY_SIZE(valid_properties));
+}
+
+static bool si476x_core_is_valid_property_a30(struct si476x_core *core,
+                                              u16 property)
+{
+        static const u16 valid_properties[] = {
+                0x071C, 0x071D,
+                0x1007, 0x1008,
+                0x220F, 0x2214,
+                0x2301,
+                0x3105, 0x3106,
+                0x3402,
+        };
+
+        static const struct si476x_property_range valid_ranges[] = {
+                { 0x0405, 0x0411 },
+                { 0x2008, 0x200B },
+                { 0x2220, 0x2223 },
+                { 0x3100, 0x3106 },
+        };
+
+        return  si476x_core_is_valid_property_a20(core, property) ||
+                si476x_core_element_is_in_range(property, valid_ranges,
+                                                ARRAY_SIZE(valid_ranges)) ||
+                si476x_core_element_is_in_array(property, valid_properties,
+                                                ARRAY_SIZE(valid_properties));
+}
+
+typedef bool (*valid_property_pred_t) (struct si476x_core *, u16);
+
+static bool si476x_core_is_valid_property(struct si476x_core *core,
+                                          u16 property)
+{
+        static const valid_property_pred_t is_valid_property[] = {
+                [SI476X_REVISION_A10] = si476x_core_is_valid_property_a10,
+                [SI476X_REVISION_A20] = si476x_core_is_valid_property_a20,
+                [SI476X_REVISION_A30] = si476x_core_is_valid_property_a30,
+        };
+
+        BUG_ON(core->revision > SI476X_REVISION_A30 ||
+               core->revision == -1);
+        return is_valid_property[core->revision](core, property);
+}
+
+
+static bool si476x_core_is_readonly_property(struct si476x_core *core,
+                                             u16 property)
+{
+        BUG_ON(core->revision > SI476X_REVISION_A30 ||
+               core->revision == -1);
+
+        switch (core->revision) {
+        case SI476X_REVISION_A10:
+                return (property == 0x3200);
+        case SI476X_REVISION_A20:
+                return (property == 0x1006 ||
+                        property == 0x2210 ||
+                        property == 0x3200);
+        case SI476X_REVISION_A30:
+                return false;
+        }
+
+        return false;
+}
+
+static bool si476x_core_regmap_readable_register(struct device *dev,
+                                                 unsigned int reg)
+{
+        struct i2c_client *client = to_i2c_client(dev);
+        struct si476x_core *core = i2c_get_clientdata(client);
+
+        return si476x_core_is_valid_property(core, (u16) reg);
+
+}
+
+static bool si476x_core_regmap_writable_register(struct device *dev,
+                                                 unsigned int reg)
+{
+        struct i2c_client *client = to_i2c_client(dev);
+        struct si476x_core *core = i2c_get_clientdata(client);
+
+        return si476x_core_is_valid_property(core, (u16) reg) &&
+                !si476x_core_is_readonly_property(core, (u16) reg);
+}
+
+
+static int si476x_core_regmap_write(void *context, unsigned int reg,
+                                    unsigned int val)
+{
+        return si476x_core_cmd_set_property(context, reg, val);
+}
+
+static int si476x_core_regmap_read(void *context, unsigned int reg,
+                                   unsigned *val)
+{
+        struct si476x_core *core = context;
+        int err;
+
+        err = si476x_core_cmd_get_property(core, reg);
+        if (err < 0)
+                return err;
+
+        *val = err;
+
+        return 0;
+}
+
+
+static const struct regmap_config si476x_regmap_config = {
+        .reg_bits = 16,
+        .val_bits = 16,
+
+        .max_register = 0x4003,
+
+        .writeable_reg = si476x_core_regmap_writable_register,
+        .readable_reg = si476x_core_regmap_readable_register,
+
+        .reg_read = si476x_core_regmap_read,
+        .reg_write = si476x_core_regmap_write,
+
+        .cache_type = REGCACHE_RBTREE,
+};
+
+struct regmap *devm_regmap_init_si476x(struct si476x_core *core)
+{
+        return devm_regmap_init(&core->client->dev, NULL,
+                                core, &si476x_regmap_config);
+}
+EXPORT_SYMBOL_GPL(devm_regmap_init_si476x);