V4L/DVB (12182): cx18: Add DVB-T support for Yuan MPC-718 cards with an MT352 or ZL10353

Add DVB-T support for Yuan MPC-718 cards with an MT352 or ZL10353 demodulator.

There are apparently some units with a DiBcom demodulator which could be
supported by one of the dib7000 modules - but this is not implemented in the
cx18 driver (yet).

Due to lack of porgramming details for the MT352 and the mt352 module requiring
a "demod_init" function, a "firmware" must be obtained and loaded to get
DVB-T working for Yuan MPC-718 cards with an MT352.
Tested-by: Steve Firth <firth650@btinternet.com>
Signed-off-by: Andy Walls <awalls@radix.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/video/cx18/cx18-cards.c

@@ -204,8 +204,8 @@ static const struct cx18_card cx18_card_mpc718 = {
 	.v4l2_capabilities = CX18_CAP_ENCODER,
 	.hw_audio_ctrl = CX18_HW_418_AV,
 	.hw_muxer = CX18_HW_GPIO_MUX,
-	.hw_all = CX18_HW_418_AV | CX18_HW_TUNER | CX18_HW_GPIO_MUX |
-		  CX18_HW_GPIO_RESET_CTRL,
+	.hw_all = CX18_HW_418_AV | CX18_HW_TUNER |
+		  CX18_HW_GPIO_MUX | CX18_HW_DVB | CX18_HW_GPIO_RESET_CTRL,
 	.video_inputs = {
 		{ CX18_CARD_INPUT_VID_TUNER,  0, CX18_AV_COMPOSITE2 },
 		{ CX18_CARD_INPUT_SVIDEO1,    1,

drivers/media/video/cx18/cx18-dvb.c

@@ -30,6 +30,10 @@
 #include "s5h1409.h"
 #include "mxl5005s.h"
 #include "zl10353.h"
+
+#include <linux/firmware.h>
+#include "mt352.h"
+#include "mt352_priv.h"
 #include "tuner-xc2028.h"
 
 DVB_DEFINE_MOD_OPT_ADAPTER_NR(adapter_nr);
@@ -38,6 +42,11 @@ DVB_DEFINE_MOD_OPT_ADAPTER_NR(adapter_nr);
 #define CX18_CLOCK_ENABLE2		 0xc71024
 #define CX18_DMUX_CLK_MASK		 0x0080
 
+/*
+ * CX18_CARD_HVR_1600_ESMT
+ * CX18_CARD_HVR_1600_SAMSUNG
+ */
+
 static struct mxl5005s_config hauppauge_hvr1600_tuner = {
 	.i2c_address     = 0xC6 >> 1,
 	.if_freq         = IF_FREQ_5380000HZ,
@@ -65,6 +74,9 @@ static struct s5h1409_config hauppauge_hvr1600_config = {
 	.mpeg_timing   = S5H1409_MPEGTIMING_CONTINOUS_NONINVERTING_CLOCK
 };
 
+/*
+ * CX18_CARD_LEADTEK_DVR3100H
+ */
 /* Information/confirmation of proper config values provided by Terry Wu */
 static struct zl10353_config leadtek_dvr3100h_demod = {
 	.demod_address         = 0x1e >> 1, /* Datasheet suggested straps */
@@ -74,6 +86,121 @@ static struct zl10353_config leadtek_dvr3100h_demod = {
 	.disable_i2c_gate_ctrl = 1,         /* Disable the I2C gate */
 };
 
+/*
+ * CX18_CARD_YUAN_MPC718
+ */
+/*
+ * Due to
+ *
+ * 1. an absence of information on how to prgram the MT352
+ * 2. the Linux mt352 module pushing MT352 initialzation off onto us here
+ *
+ * We have to use an init sequence that *you* must extract from the Windows
+ * driver (yuanrap.sys) and which we load as a firmware.
+ *
+ * If someone can provide me with a Zarlink MT352 (Intel CE6352?) Design Manual
+ * with chip programming details, then I can remove this annoyance.
+ */
+static int yuan_mpc718_mt352_reqfw(struct cx18_stream *stream,
+				   const struct firmware **fw)
+{
+	struct cx18 *cx = stream->cx;
+	const char *fn = "dvb-cx18-mpc718-mt352.fw";
+	int ret;
+
+	ret = request_firmware(fw, fn, &cx->pci_dev->dev);
+	if (ret)
+		CX18_ERR("Unable to open firmware file %s\n", fn);
+	else {
+		size_t sz = (*fw)->size;
+		if (sz < 2 || sz > 64 || (sz % 2) != 0) {
+			CX18_ERR("Firmware %s has a bad size: %lu bytes\n",
+				 fn, (unsigned long) sz);
+			ret = -EILSEQ;
+			release_firmware(*fw);
+			*fw = NULL;
+		}
+	}
+
+	if (ret) {
+		CX18_ERR("The MPC718 board variant with the MT352 DVB-T"
+			  "demodualtor will not work without it\n");
+		CX18_ERR("Run 'linux/Documentation/dvb/get_dvb_firmware "
+			  "mpc718' if you need the firmware\n");
+	}
+	return ret;
+}
+
+static int yuan_mpc718_mt352_init(struct dvb_frontend *fe)
+{
+	struct cx18_dvb *dvb = container_of(fe->dvb,
+					    struct cx18_dvb, dvb_adapter);
+	struct cx18_stream *stream = container_of(dvb, struct cx18_stream, dvb);
+	const struct firmware *fw = NULL;
+	int ret;
+	int i;
+	u8 buf[3];
+
+	ret = yuan_mpc718_mt352_reqfw(stream, &fw);
+	if (ret)
+		return ret;
+
+	/* Loop through all the register-value pairs in the firmware file */
+	for (i = 0; i < fw->size; i += 2) {
+		buf[0] = fw->data[i];
+		/* Intercept a few registers we want to set ourselves */
+		switch (buf[0]) {
+		case TRL_NOMINAL_RATE_0:
+			/* Set our custom OFDM bandwidth in the case below */
+			break;
+		case TRL_NOMINAL_RATE_1:
+			/* 6 MHz: 64/7 * 6/8 / 20.48 * 2^16 = 0x55b6.db6 */
+			/* 7 MHz: 64/7 * 7/8 / 20.48 * 2^16 = 0x6400 */
+			/* 8 MHz: 64/7 * 8/8 / 20.48 * 2^16 = 0x7249.249 */
+			buf[1] = 0x72;
+			buf[2] = 0x49;
+			mt352_write(fe, buf, 3);
+			break;
+		case INPUT_FREQ_0:
+			/* Set our custom IF in the case below */
+			break;
+		case INPUT_FREQ_1:
+			/* 4.56 MHz IF: (20.48 - 4.56)/20.48 * 2^14 = 0x31c0 */
+			buf[1] = 0x31;
+			buf[2] = 0xc0;
+			mt352_write(fe, buf, 3);
+			break;
+		default:
+			/* Pass through the register-value pair from the fw */
+			buf[1] = fw->data[i+1];
+			mt352_write(fe, buf, 2);
+			break;
+		}
+	}
+
+	buf[0] = (u8) TUNER_GO;
+	buf[1] = 0x01; /* Go */
+	mt352_write(fe, buf, 2);
+	release_firmware(fw);
+	return 0;
+}
+
+static struct mt352_config yuan_mpc718_mt352_demod = {
+	.demod_address = 0x1e >> 1,
+	.adc_clock     = 20480,     /* 20.480 MHz */
+	.if2           =  4560,     /*  4.560 MHz */
+	.no_tuner      = 1,         /* XC3028 is not behind the gate */
+	.demod_init    = yuan_mpc718_mt352_init,
+};
+
+static struct zl10353_config yuan_mpc718_zl10353_demod = {
+	.demod_address         = 0x1e >> 1, /* Datasheet suggested straps */
+	.if2                   = 45600,     /* 4.560 MHz IF from the XC3028 */
+	.parallel_ts           = 1,         /* Not a serial TS */
+	.no_tuner              = 1,         /* XC3028 is not behind the gate */
+	.disable_i2c_gate_ctrl = 1,         /* Disable the I2C gate */
+};
+
 static int dvb_register(struct cx18_stream *stream);
 
 /* Kernel DVB framework calls this when the feed needs to start.
@@ -113,6 +240,7 @@ static int cx18_dvb_start_feed(struct dvb_demux_feed *feed)
 		break;
 
 	case CX18_CARD_LEADTEK_DVR3100H:
+	case CX18_CARD_YUAN_MPC718:
 	default:
 		/* Assumption - Parallel transport - Signalling
 		 * undefined or default.
@@ -326,6 +454,38 @@ static int dvb_register(struct cx18_stream *stream)
 				fe->ops.tuner_ops.set_config(fe, &ctrl);
 		}
 		break;
+	case CX18_CARD_YUAN_MPC718:
+		/*
+		 * TODO
+		 * Apparently, these cards also could instead have a
+		 * DiBcom demod supported by one of the db7000 drivers
+		 */
+		dvb->fe = dvb_attach(mt352_attach,
+				     &yuan_mpc718_mt352_demod,
+				     &cx->i2c_adap[1]);
+		if (dvb->fe == NULL)
+			dvb->fe = dvb_attach(zl10353_attach,
+					     &yuan_mpc718_zl10353_demod,
+					     &cx->i2c_adap[1]);
+		if (dvb->fe != NULL) {
+			struct dvb_frontend *fe;
+			struct xc2028_config cfg = {
+				.i2c_adap = &cx->i2c_adap[1],
+				.i2c_addr = 0xc2 >> 1,
+				.ctrl = NULL,
+			};
+			static struct xc2028_ctrl ctrl = {
+				.fname   = XC2028_DEFAULT_FIRMWARE,
+				.max_len = 64,
+				.demod   = XC3028_FE_ZARLINK456,
+				.type    = XC2028_AUTO,
+			};
+
+			fe = dvb_attach(xc2028_attach, dvb->fe, &cfg);
+			if (fe != NULL && fe->ops.tuner_ops.set_config != NULL)
+				fe->ops.tuner_ops.set_config(fe, &ctrl);
+		}
+		break;
 	default:
 		/* No Digital Tv Support */
 		break;