// SPDX-License-Identifier: GPL-2.0-only
/*
 *   Sharp VA3A5JZ921 One Seg Broadcast Module driver
 *   This device is labeled as just S. 921 at the top of the frontend can
 *
 *   Copyright (C) 2009-2010 Mauro Carvalho Chehab
 *   Copyright (C) 2009-2010 Douglas Landgraf <dougsland@redhat.com>
 *
 *   Developed for Leadership SBTVD 1seg device sold in Brazil
 *
 *   Frontend module based on cx24123 driver, getting some info from
 *      the old s921 driver.
 *
 *   FIXME: Need to port to DVB v5.2 API
 */

#include <linux/kernel.h>
#include <asm/div64.h>

#include <media/dvb_frontend.h>
#include "s921.h"

static int debug = 1;
module_param(debug, int, 0644);
MODULE_PARM_DESC(debug, "Activates frontend debugging (default:0)");

#define rc(args...)  do {                                               \
        printk(KERN_ERR  "s921: " args);                                \
} while (0)

#define dprintk(args...)                                                \
        do {                                                            \
                if (debug) {                                            \
                        printk(KERN_DEBUG "s921: %s: ", __func__);      \
                        printk(args);                                   \
                }                                                       \
        } while (0)

struct s921_state {
        struct i2c_adapter *i2c;
        const struct s921_config *config;

        struct dvb_frontend frontend;

        /* The Demod can't easily provide these, we cache them */
        u32 currentfreq;
};

/*
 * Various tuner defaults need to be established for a given frequency kHz.
 * fixme: The bounds on the bands do not match the doc in real life.
 * fixme: Some of them have been moved, other might need adjustment.
 */
static struct s921_bandselect_val {
        u32 freq_low;
        u8  band_reg;
} s921_bandselect[] = {
        {         0, 0x7b },
        { 485140000, 0x5b },
        { 515140000, 0x3b },
        { 545140000, 0x1b },
        { 599140000, 0xfb },
        { 623140000, 0xdb },
        { 659140000, 0xbb },
        { 713140000, 0x9b },
};

struct regdata {
        u8 reg;
        u8 data;
};

static struct regdata s921_init[] = {
        { 0x01, 0x80 },         /* Probably, a reset sequence */
        { 0x01, 0x40 },
        { 0x01, 0x80 },
        { 0x01, 0x40 },

        { 0x02, 0x00 },
        { 0x03, 0x40 },
        { 0x04, 0x01 },
        { 0x05, 0x00 },
        { 0x06, 0x00 },
        { 0x07, 0x00 },
        { 0x08, 0x00 },
        { 0x09, 0x00 },
        { 0x0a, 0x00 },
        { 0x0b, 0x5a },
        { 0x0c, 0x00 },
        { 0x0d, 0x00 },
        { 0x0f, 0x00 },
        { 0x13, 0x1b },
        { 0x14, 0x80 },
        { 0x15, 0x40 },
        { 0x17, 0x70 },
        { 0x18, 0x01 },
        { 0x19, 0x12 },
        { 0x1a, 0x01 },
        { 0x1b, 0x12 },
        { 0x1c, 0xa0 },
        { 0x1d, 0x00 },
        { 0x1e, 0x0a },
        { 0x1f, 0x08 },
        { 0x20, 0x40 },
        { 0x21, 0xff },
        { 0x22, 0x4c },
        { 0x23, 0x4e },
        { 0x24, 0x4c },
        { 0x25, 0x00 },
        { 0x26, 0x00 },
        { 0x27, 0xf4 },
        { 0x28, 0x60 },
        { 0x29, 0x88 },
        { 0x2a, 0x40 },
        { 0x2b, 0x40 },
        { 0x2c, 0xff },
        { 0x2d, 0x00 },
        { 0x2e, 0xff },
        { 0x2f, 0x00 },
        { 0x30, 0x20 },
        { 0x31, 0x06 },
        { 0x32, 0x0c },
        { 0x34, 0x0f },
        { 0x37, 0xfe },
        { 0x38, 0x00 },
        { 0x39, 0x63 },
        { 0x3a, 0x10 },
        { 0x3b, 0x10 },
        { 0x47, 0x00 },
        { 0x49, 0xe5 },
        { 0x4b, 0x00 },
        { 0x50, 0xc0 },
        { 0x52, 0x20 },
        { 0x54, 0x5a },
        { 0x55, 0x5b },
        { 0x56, 0x40 },
        { 0x57, 0x70 },
        { 0x5c, 0x50 },
        { 0x5d, 0x00 },
        { 0x62, 0x17 },
        { 0x63, 0x2f },
        { 0x64, 0x6f },
        { 0x68, 0x00 },
        { 0x69, 0x89 },
        { 0x6a, 0x00 },
        { 0x6b, 0x00 },
        { 0x6c, 0x00 },
        { 0x6d, 0x00 },
        { 0x6e, 0x00 },
        { 0x70, 0x10 },
        { 0x71, 0x00 },
        { 0x75, 0x00 },
        { 0x76, 0x30 },
        { 0x77, 0x01 },
        { 0xaf, 0x00 },
        { 0xb0, 0xa0 },
        { 0xb2, 0x3d },
        { 0xb3, 0x25 },
        { 0xb4, 0x8b },
        { 0xb5, 0x4b },
        { 0xb6, 0x3f },
        { 0xb7, 0xff },
        { 0xb8, 0xff },
        { 0xb9, 0xfc },
        { 0xba, 0x00 },
        { 0xbb, 0x00 },
        { 0xbc, 0x00 },
        { 0xd0, 0x30 },
        { 0xe4, 0x84 },
        { 0xf0, 0x48 },
        { 0xf1, 0x19 },
        { 0xf2, 0x5a },
        { 0xf3, 0x8e },
        { 0xf4, 0x2d },
        { 0xf5, 0x07 },
        { 0xf6, 0x5a },
        { 0xf7, 0xba },
        { 0xf8, 0xd7 },
};

static struct regdata s921_prefreq[] = {
        { 0x47, 0x60 },
        { 0x68, 0x00 },
        { 0x69, 0x89 },
        { 0xf0, 0x48 },
        { 0xf1, 0x19 },
};

static struct regdata s921_postfreq[] = {
        { 0xf5, 0xae },
        { 0xf6, 0xb7 },
        { 0xf7, 0xba },
        { 0xf8, 0xd7 },
        { 0x68, 0x0a },
        { 0x69, 0x09 },
};

static int s921_i2c_writereg(struct s921_state *state,
                             u8 i2c_addr, int reg, int data)
{
        u8 buf[] = { reg, data };
        struct i2c_msg msg = {
                .addr = i2c_addr, .flags = 0, .buf = buf, .len = 2
        };
        int rc;

        rc = i2c_transfer(state->i2c, &msg, 1);
        if (rc != 1) {
                printk("%s: writereg rcor(rc == %i, reg == 0x%02x, data == 0x%02x)\n",
                       __func__, rc, reg, data);
                return rc;
        }

        return 0;
}

static int s921_i2c_writeregdata(struct s921_state *state, u8 i2c_addr,
                                 struct regdata *rd, int size)
{
        int i, rc;

        for (i = 0; i < size; i++) {
                rc = s921_i2c_writereg(state, i2c_addr, rd[i].reg, rd[i].data);
                if (rc < 0)
                        return rc;
        }
        return 0;
}

static int s921_i2c_readreg(struct s921_state *state, u8 i2c_addr, u8 reg)
{
        u8 val;
        int rc;
        struct i2c_msg msg[] = {
                { .addr = i2c_addr, .flags = 0, .buf = &reg, .len = 1 },
                { .addr = i2c_addr, .flags = I2C_M_RD, .buf = &val, .len = 1 }
        };

        rc = i2c_transfer(state->i2c, msg, 2);

        if (rc != 2) {
                rc("%s: reg=0x%x (rcor=%d)\n", __func__, reg, rc);
                return rc;
        }

        return val;
}

#define s921_readreg(state, reg) \
        s921_i2c_readreg(state, state->config->demod_address, reg)
#define s921_writereg(state, reg, val) \
        s921_i2c_writereg(state, state->config->demod_address, reg, val)
#define s921_writeregdata(state, regdata) \
        s921_i2c_writeregdata(state, state->config->demod_address, \
        regdata, ARRAY_SIZE(regdata))

static int s921_pll_tune(struct dvb_frontend *fe)
{
        struct dtv_frontend_properties *p = &fe->dtv_property_cache;
        struct s921_state *state = fe->demodulator_priv;
        int band, rc, i;
        unsigned long f_offset;
        u8 f_switch;
        u64 offset;

        dprintk("frequency=%i\n", p->frequency);

        for (band = 0; band < ARRAY_SIZE(s921_bandselect); band++)
                if (p->frequency < s921_bandselect[band].freq_low)
                        break;
        band--;

        if (band < 0) {
                rc("%s: frequency out of range\n", __func__);
                return -EINVAL;
        }

        f_switch = s921_bandselect[band].band_reg;

        offset = ((u64)p->frequency) * 258;
        do_div(offset, 6000000);
        f_offset = ((unsigned long)offset) + 2321;

        rc = s921_writeregdata(state, s921_prefreq);
        if (rc < 0)
                return rc;

        rc = s921_writereg(state, 0xf2, (f_offset >> 8) & 0xff);
        if (rc < 0)
                return rc;

        rc = s921_writereg(state, 0xf3, f_offset & 0xff);
        if (rc < 0)
                return rc;

        rc = s921_writereg(state, 0xf4, f_switch);
        if (rc < 0)
                return rc;

        rc = s921_writeregdata(state, s921_postfreq);
        if (rc < 0)
                return rc;

        for (i = 0 ; i < 6; i++) {
                rc = s921_readreg(state, 0x80);
                dprintk("status 0x80: %02x\n", rc);
        }
        rc = s921_writereg(state, 0x01, 0x40);
        if (rc < 0)
                return rc;

        rc = s921_readreg(state, 0x01);
        dprintk("status 0x01: %02x\n", rc);

        rc = s921_readreg(state, 0x80);
        dprintk("status 0x80: %02x\n", rc);

        rc = s921_readreg(state, 0x80);
        dprintk("status 0x80: %02x\n", rc);

        rc = s921_readreg(state, 0x32);
        dprintk("status 0x32: %02x\n", rc);

        dprintk("pll tune band=%d, pll=%d\n", f_switch, (int)f_offset);

        return 0;
}

static int s921_initfe(struct dvb_frontend *fe)
{
        struct s921_state *state = fe->demodulator_priv;
        int rc;

        dprintk("\n");

        rc = s921_writeregdata(state, s921_init);
        if (rc < 0)
                return rc;

        return 0;
}

static int s921_read_status(struct dvb_frontend *fe, enum fe_status *status)
{
        struct s921_state *state = fe->demodulator_priv;
        int regstatus, rc;

        *status = 0;

        rc = s921_readreg(state, 0x81);
        if (rc < 0)
                return rc;

        regstatus = rc << 8;

        rc = s921_readreg(state, 0x82);
        if (rc < 0)
                return rc;

        regstatus |= rc;

        dprintk("status = %04x\n", regstatus);

        /* Full Sync - We don't know what each bit means on regs 0x81/0x82 */
        if ((regstatus & 0xff) == 0x40) {
                *status = FE_HAS_SIGNAL  |
                          FE_HAS_CARRIER |
                          FE_HAS_VITERBI |
                          FE_HAS_SYNC    |
                          FE_HAS_LOCK;
        } else if (regstatus & 0x40) {
                /* This is close to Full Sync, but not enough to get useful info */
                *status = FE_HAS_SIGNAL  |
                          FE_HAS_CARRIER |
                          FE_HAS_VITERBI |
                          FE_HAS_SYNC;
        }

        return 0;
}

static int s921_read_signal_strength(struct dvb_frontend *fe, u16 *strength)
{
        enum fe_status  status;
        struct s921_state *state = fe->demodulator_priv;
        int rc;

        /* FIXME: Use the proper register for it... 0x80? */
        rc = s921_read_status(fe, &status);
        if (rc < 0)
                return rc;

        *strength = (status & FE_HAS_LOCK) ? 0xffff : 0;

        dprintk("strength = 0x%04x\n", *strength);

        rc = s921_readreg(state, 0x01);
        dprintk("status 0x01: %02x\n", rc);

        rc = s921_readreg(state, 0x80);
        dprintk("status 0x80: %02x\n", rc);

        rc = s921_readreg(state, 0x32);
        dprintk("status 0x32: %02x\n", rc);

        return 0;
}

static int s921_set_frontend(struct dvb_frontend *fe)
{
        struct dtv_frontend_properties *p = &fe->dtv_property_cache;
        struct s921_state *state = fe->demodulator_priv;
        int rc;

        dprintk("\n");

        /* FIXME: We don't know how to use non-auto mode */

        rc = s921_pll_tune(fe);
        if (rc < 0)
                return rc;

        state->currentfreq = p->frequency;

        return 0;
}

static int s921_get_frontend(struct dvb_frontend *fe,
                             struct dtv_frontend_properties *p)
{
        struct s921_state *state = fe->demodulator_priv;

        /* FIXME: Probably it is possible to get it from regs f1 and f2 */
        p->frequency = state->currentfreq;
        p->delivery_system = SYS_ISDBT;

        return 0;
}

static int s921_tune(struct dvb_frontend *fe,
                        bool re_tune,
                        unsigned int mode_flags,
                        unsigned int *delay,
                        enum fe_status *status)
{
        int rc = 0;

        dprintk("\n");

        if (re_tune)
                rc = s921_set_frontend(fe);

        if (!(mode_flags & FE_TUNE_MODE_ONESHOT))
                s921_read_status(fe, status);

        return rc;
}

static enum dvbfe_algo s921_get_algo(struct dvb_frontend *fe)
{
        return DVBFE_ALGO_HW;
}

static void s921_release(struct dvb_frontend *fe)
{
        struct s921_state *state = fe->demodulator_priv;

        dprintk("\n");
        kfree(state);
}

static const struct dvb_frontend_ops s921_ops;

struct dvb_frontend *s921_attach(const struct s921_config *config,
                                    struct i2c_adapter *i2c)
{
        /* allocate memory for the internal state */
        struct s921_state *state =
                kzalloc_obj(struct s921_state);

        dprintk("\n");
        if (!state) {
                rc("Unable to kzalloc\n");
                return NULL;
        }

        /* setup the state */
        state->config = config;
        state->i2c = i2c;

        /* create dvb_frontend */
        memcpy(&state->frontend.ops, &s921_ops,
                sizeof(struct dvb_frontend_ops));
        state->frontend.demodulator_priv = state;

        return &state->frontend;
}
EXPORT_SYMBOL_GPL(s921_attach);

static const struct dvb_frontend_ops s921_ops = {
        .delsys = { SYS_ISDBT },
        /* Use dib8000 values per default */
        .info = {
                .name = "Sharp S921",
                .frequency_min_hz = 470 * MHz,
                /*
                 * Max should be 770MHz instead, according with Sharp docs,
                 * but Leadership doc says it works up to 806 MHz. This is
                 * required to get channel 69, used in Brazil
                 */
                .frequency_max_hz = 806 * MHz,
                .caps =  FE_CAN_INVERSION_AUTO |
                         FE_CAN_FEC_1_2  | FE_CAN_FEC_2_3 | FE_CAN_FEC_3_4 |
                         FE_CAN_FEC_5_6  | FE_CAN_FEC_7_8 | FE_CAN_FEC_AUTO |
                         FE_CAN_QPSK     | FE_CAN_QAM_16 | FE_CAN_QAM_64 |
                         FE_CAN_QAM_AUTO | FE_CAN_TRANSMISSION_MODE_AUTO |
                         FE_CAN_GUARD_INTERVAL_AUTO | FE_CAN_RECOVER |
                         FE_CAN_HIERARCHY_AUTO,
        },

        .release = s921_release,

        .init = s921_initfe,
        .set_frontend = s921_set_frontend,
        .get_frontend = s921_get_frontend,
        .read_status = s921_read_status,
        .read_signal_strength = s921_read_signal_strength,
        .tune = s921_tune,
        .get_frontend_algo = s921_get_algo,
};

MODULE_DESCRIPTION("DVB Frontend module for Sharp S921 hardware");
MODULE_AUTHOR("Mauro Carvalho Chehab");
MODULE_AUTHOR("Douglas Landgraf <dougsland@redhat.com>");
MODULE_LICENSE("GPL");