[media] mxl301rf: add driver for MaxLinear MxL301RF OFDM tuner

This patch adds driver for mxl301rf OFDM tuner chips.
It is used as an ISDB-T tuner in earthsoft pt3 cards.

Note that this driver does not initilize the chip,
because the initilization sequence / register setting is not disclosed.
Thus, the driver assumes that the chips are initilized externally
by its parent board driver before tuner_ops->init() are called,
like in PT3 driver where the bridge chip contains the init sequence
in its private memory and provides a command to trigger the sequence.

Signed-off-by: Akihiro Tsukada <tskd08@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

1 files changed, 349 insertions, 0 deletions

diff --git a/drivers/media/tuners/mxl301rf.c b/drivers/media/tuners/mxl301rf.c
new file mode 100644
index 000000000000..1575a5db776a
--- /dev/null
+++ b/drivers/media/tuners/mxl301rf.c
@@ -0,0 +1,349 @@
+/*
+ * MaxLinear MxL301RF OFDM tuner driver
+ *
+ * Copyright (C) 2014 Akihiro Tsukada <tskd08@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.
+ *
+ *
+ * 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.
+ */
+
+/*
+ * NOTICE:
+ * This driver is incomplete and lacks init/config of the chips,
+ * as the necessary info is not disclosed.
+ * Other features like get_if_frequency() are missing as well.
+ * It assumes that users of this driver (such as a PCI bridge of
+ * DTV receiver cards) properly init and configure the chip
+ * via I2C *before* calling this driver's init() function.
+ *
+ * Currently, PT3 driver is the only one that uses this driver,
+ * and contains init/config code in its firmware.
+ * Thus some part of the code might be dependent on PT3 specific config.
+ */
+
+#include <linux/kernel.h>
+#include "mxl301rf.h"
+
+struct mxl301rf_state {
+        struct mxl301rf_config cfg;
+        struct i2c_client *i2c;
+};
+
+static struct mxl301rf_state *cfg_to_state(struct mxl301rf_config *c)
+{
+        return container_of(c, struct mxl301rf_state, cfg);
+}
+
+static int raw_write(struct mxl301rf_state *state, const u8 *buf, int len)
+{
+        int ret;
+
+        ret = i2c_master_send(state->i2c, buf, len);
+        if (ret >= 0 && ret < len)
+                ret = -EIO;
+        return (ret == len) ? 0 : ret;
+}
+
+static int reg_write(struct mxl301rf_state *state, u8 reg, u8 val)
+{
+        u8 buf[2] = { reg, val };
+
+        return raw_write(state, buf, 2);
+}
+
+static int reg_read(struct mxl301rf_state *state, u8 reg, u8 *val)
+{
+        u8 wbuf[2] = { 0xfb, reg };
+        int ret;
+
+        ret = raw_write(state, wbuf, sizeof(wbuf));
+        if (ret == 0)
+                ret = i2c_master_recv(state->i2c, val, 1);
+        if (ret >= 0 && ret < 1)
+                ret = -EIO;
+        return (ret == 1) ? 0 : ret;
+}
+
+/* tuner_ops */
+
+/* get RSSI and update propery cache, set to *out in % */
+static int mxl301rf_get_rf_strength(struct dvb_frontend *fe, u16 *out)
+{
+        struct mxl301rf_state *state;
+        int ret;
+        u8  rf_in1, rf_in2, rf_off1, rf_off2;
+        u16 rf_in, rf_off;
+        s64 level;
+        struct dtv_fe_stats *rssi;
+
+        rssi = &fe->dtv_property_cache.strength;
+        rssi->len = 1;
+        rssi->stat[0].scale = FE_SCALE_NOT_AVAILABLE;
+        *out = 0;
+
+        state = fe->tuner_priv;
+        ret = reg_write(state, 0x14, 0x01);
+        if (ret < 0)
+                return ret;
+        usleep_range(1000, 2000);
+
+        ret = reg_read(state, 0x18, &rf_in1);
+        if (ret == 0)
+                ret = reg_read(state, 0x19, &rf_in2);
+        if (ret == 0)
+                ret = reg_read(state, 0xd6, &rf_off1);
+        if (ret == 0)
+                ret = reg_read(state, 0xd7, &rf_off2);
+        if (ret != 0)
+                return ret;
+
+        rf_in = (rf_in2 & 0x07) << 8 | rf_in1;
+        rf_off = (rf_off2 & 0x0f) << 5 | (rf_off1 >> 3);
+        level = rf_in - rf_off - (113 << 3); /* x8 dBm */
+        level = level * 1000 / 8;
+        rssi->stat[0].svalue = level;
+        rssi->stat[0].scale = FE_SCALE_DECIBEL;
+        /* *out = (level - min) * 100 / (max - min) */
+        *out = (rf_in - rf_off + (1 << 9) - 1) * 100 / ((5 << 9) - 2);
+        return 0;
+}
+
+/* spur shift parameters */
+struct shf {
+        u32     freq;           /* Channel center frequency */
+        u32     ofst_th;        /* Offset frequency threshold */
+        u8      shf_val;        /* Spur shift value */
+        u8      shf_dir;        /* Spur shift direction */
+};
+
+static const struct shf shf_tab[] = {
+        {  64500, 500, 0x92, 0x07 },
+        { 191500, 300, 0xe2, 0x07 },
+        { 205500, 500, 0x2c, 0x04 },
+        { 212500, 500, 0x1e, 0x04 },
+        { 226500, 500, 0xd4, 0x07 },
+        {  99143, 500, 0x9c, 0x07 },
+        { 173143, 500, 0xd4, 0x07 },
+        { 191143, 300, 0xd4, 0x07 },
+        { 207143, 500, 0xce, 0x07 },
+        { 225143, 500, 0xce, 0x07 },
+        { 243143, 500, 0xd4, 0x07 },
+        { 261143, 500, 0xd4, 0x07 },
+        { 291143, 500, 0xd4, 0x07 },
+        { 339143, 500, 0x2c, 0x04 },
+        { 117143, 500, 0x7a, 0x07 },
+        { 135143, 300, 0x7a, 0x07 },
+        { 153143, 500, 0x01, 0x07 }
+};
+
+struct reg_val {
+        u8 reg;
+        u8 val;
+} __attribute__ ((__packed__));
+
+static const struct reg_val set_idac[] = {
+        { 0x0d, 0x00 },
+        { 0x0c, 0x67 },
+        { 0x6f, 0x89 },
+        { 0x70, 0x0c },
+        { 0x6f, 0x8a },
+        { 0x70, 0x0e },
+        { 0x6f, 0x8b },
+        { 0x70, 0x1c },
+};
+
+static int mxl301rf_set_params(struct dvb_frontend *fe)
+{
+        struct reg_val tune0[] = {
+                { 0x13, 0x00 },         /* abort tuning */
+                { 0x3b, 0xc0 },
+                { 0x3b, 0x80 },
+                { 0x10, 0x95 },         /* BW */
+                { 0x1a, 0x05 },
+                { 0x61, 0x00 },         /* spur shift value (placeholder) */
+                { 0x62, 0xa0 }          /* spur shift direction (placeholder) */
+        };
+
+        struct reg_val tune1[] = {
+                { 0x11, 0x40 },         /* RF frequency L (placeholder) */
+                { 0x12, 0x0e },         /* RF frequency H (placeholder) */
+                { 0x13, 0x01 }          /* start tune */
+        };
+
+        struct mxl301rf_state *state;
+        u32 freq;
+        u16 f;
+        u32 tmp, div;
+        int i, ret;
+
+        state = fe->tuner_priv;
+        freq = fe->dtv_property_cache.frequency;
+
+        /* spur shift function (for analog) */
+        for (i = 0; i < ARRAY_SIZE(shf_tab); i++) {
+                if (freq >= (shf_tab[i].freq - shf_tab[i].ofst_th) * 1000 &&
+                    freq <= (shf_tab[i].freq + shf_tab[i].ofst_th) * 1000) {
+                        tune0[5].val = shf_tab[i].shf_val;
+                        tune0[6].val = 0xa0 | shf_tab[i].shf_dir;
+                        break;
+                }
+        }
+        ret = raw_write(state, (u8 *) tune0, sizeof(tune0));
+        if (ret < 0)
+                goto failed;
+        usleep_range(3000, 4000);
+
+        /* convert freq to 10.6 fixed point float [MHz] */
+        f = freq / 1000000;
+        tmp = freq % 1000000;
+        div = 1000000;
+        for (i = 0; i < 6; i++) {
+                f <<= 1;
+                div >>= 1;
+                if (tmp > div) {
+                        tmp -= div;
+                        f |= 1;
+                }
+        }
+        if (tmp > 7812)
+                f++;
+        tune1[0].val = f & 0xff;
+        tune1[1].val = f >> 8;
+        ret = raw_write(state, (u8 *) tune1, sizeof(tune1));
+        if (ret < 0)
+                goto failed;
+        msleep(31);
+
+        ret = reg_write(state, 0x1a, 0x0d);
+        if (ret < 0)
+                goto failed;
+        ret = raw_write(state, (u8 *) set_idac, sizeof(set_idac));
+        if (ret < 0)
+                goto failed;
+        return 0;
+
+failed:
+        dev_warn(&state->i2c->dev, "(%s) failed. [adap%d-fe%d]\n",
+                __func__, fe->dvb->num, fe->id);
+        return ret;
+}
+
+static const struct reg_val standby_data[] = {
+        { 0x01, 0x00 },
+        { 0x13, 0x00 }
+};
+
+static int mxl301rf_sleep(struct dvb_frontend *fe)
+{
+        struct mxl301rf_state *state;
+        int ret;
+
+        state = fe->tuner_priv;
+        ret = raw_write(state, (u8 *)standby_data, sizeof(standby_data));
+        if (ret < 0)
+                dev_warn(&state->i2c->dev, "(%s) failed. [adap%d-fe%d]\n",
+                        __func__, fe->dvb->num, fe->id);
+        return ret;
+}
+
+
+/* init sequence is not public.
+ * the parent must have init'ed the device.
+ * just wake up here.
+ */
+static int mxl301rf_init(struct dvb_frontend *fe)
+{
+        struct mxl301rf_state *state;
+        int ret;
+
+        state = fe->tuner_priv;
+
+        ret = reg_write(state, 0x01, 0x01);
+        if (ret < 0) {
+                dev_warn(&state->i2c->dev, "(%s) failed. [adap%d-fe%d]\n",
+                         __func__, fe->dvb->num, fe->id);
+                return ret;
+        }
+        return 0;
+}
+
+/* I2C driver functions */
+
+static const struct dvb_tuner_ops mxl301rf_ops = {
+        .info = {
+                .name = "MaxLinear MxL301RF",
+
+                .frequency_min =  93000000,
+                .frequency_max = 803142857,
+        },
+
+        .init = mxl301rf_init,
+        .sleep = mxl301rf_sleep,
+
+        .set_params = mxl301rf_set_params,
+        .get_rf_strength = mxl301rf_get_rf_strength,
+};
+
+
+static int mxl301rf_probe(struct i2c_client *client,
+                          const struct i2c_device_id *id)
+{
+        struct mxl301rf_state *state;
+        struct mxl301rf_config *cfg;
+        struct dvb_frontend *fe;
+
+        state = kzalloc(sizeof(*state), GFP_KERNEL);
+        if (!state)
+                return -ENOMEM;
+
+        state->i2c = client;
+        cfg = client->dev.platform_data;
+
+        memcpy(&state->cfg, cfg, sizeof(state->cfg));
+        fe = cfg->fe;
+        fe->tuner_priv = state;
+        memcpy(&fe->ops.tuner_ops, &mxl301rf_ops, sizeof(mxl301rf_ops));
+
+        i2c_set_clientdata(client, &state->cfg);
+        dev_info(&client->dev, "MaxLinear MxL301RF attached.\n");
+        return 0;
+}
+
+static int mxl301rf_remove(struct i2c_client *client)
+{
+        struct mxl301rf_state *state;
+
+        state = cfg_to_state(i2c_get_clientdata(client));
+        state->cfg.fe->tuner_priv = NULL;
+        kfree(state);
+        return 0;
+}
+
+
+static const struct i2c_device_id mxl301rf_id[] = {
+        {"mxl301rf", 0},
+        {}
+};
+MODULE_DEVICE_TABLE(i2c, mxl301rf_id);
+
+static struct i2c_driver mxl301rf_driver = {
+        .driver = {
+                .name   = "mxl301rf",
+        },
+        .probe          = mxl301rf_probe,
+        .remove         = mxl301rf_remove,
+        .id_table       = mxl301rf_id,
+};
+
+module_i2c_driver(mxl301rf_driver);
+
+MODULE_DESCRIPTION("MaxLinear MXL301RF tuner");
+MODULE_AUTHOR("Akihiro TSUKADA");
+MODULE_LICENSE("GPL");