1 files changed, 280 insertions, 0 deletions
diff --git a/drivers/media/common/b2c2/flexcop-i2c.c b/drivers/media/common/b2c2/flexcop-i2c.c
new file mode 100644
index 000000000..1f1eaa807
--- /dev/null
+++ b/drivers/media/common/b2c2/flexcop-i2c.c
@@ -0,0 +1,280 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Linux driver for digital TV devices equipped with B2C2 FlexcopII(b)/III
+ * flexcop-i2c.c - flexcop internal 2Wire bus (I2C) and dvb i2c initialization
+ * see flexcop.c for copyright information
+ */
+#include "flexcop.h"
+
+#define FC_MAX_I2C_RETRIES 100000
+
+static int flexcop_i2c_operation(struct flexcop_device *fc,
+		flexcop_ibi_value *r100)
+{
+	int i;
+	flexcop_ibi_value r;
+
+	r100->tw_sm_c_100.working_start = 1;
+	deb_i2c("r100 before: %08x\n",r100->raw);
+
+	fc->write_ibi_reg(fc, tw_sm_c_100, ibi_zero);
+	fc->write_ibi_reg(fc, tw_sm_c_100, *r100); /* initiating i2c operation */
+
+	for (i = 0; i < FC_MAX_I2C_RETRIES; i++) {
+		r = fc->read_ibi_reg(fc, tw_sm_c_100);
+
+		if (!r.tw_sm_c_100.no_base_addr_ack_error) {
+			if (r.tw_sm_c_100.st_done) {
+				*r100 = r;
+				deb_i2c("i2c success\n");
+				return 0;
+			}
+		} else {
+			deb_i2c("suffering from an i2c ack_error\n");
+			return -EREMOTEIO;
+		}
+	}
+	deb_i2c("tried %d times i2c operation, never finished or too many ack errors.\n",
+		i);
+	return -EREMOTEIO;
+}
+
+static int flexcop_i2c_read4(struct flexcop_i2c_adapter *i2c,
+		flexcop_ibi_value r100, u8 *buf)
+{
+	flexcop_ibi_value r104;
+	int len = r100.tw_sm_c_100.total_bytes,
+		/* remember total_bytes is buflen-1 */
+		ret;
+
+	/* work-around to have CableStar2 and SkyStar2 rev 2.7 work
+	 * correctly:
+	 *
+	 * the ITD1000 is behind an i2c-gate which closes automatically
+	 * after an i2c-transaction the STV0297 needs 2 consecutive reads
+	 * one with no_base_addr = 0 and one with 1
+	 *
+	 * those two work-arounds are conflictin: we check for the card
+	 * type, it is set when probing the ITD1000 */
+	if (i2c->fc->dev_type == FC_SKY_REV27)
+		r100.tw_sm_c_100.no_base_addr_ack_error = i2c->no_base_addr;
+
+	ret = flexcop_i2c_operation(i2c->fc, &r100);
+	if (ret != 0) {
+		deb_i2c("Retrying operation\n");
+		r100.tw_sm_c_100.no_base_addr_ack_error = i2c->no_base_addr;
+		ret = flexcop_i2c_operation(i2c->fc, &r100);
+	}
+	if (ret != 0) {
+		deb_i2c("read failed. %d\n", ret);
+		return ret;
+	}
+
+	buf[0] = r100.tw_sm_c_100.data1_reg;
+
+	if (len > 0) {
+		r104 = i2c->fc->read_ibi_reg(i2c->fc, tw_sm_c_104);
+		deb_i2c("read: r100: %08x, r104: %08x\n", r100.raw, r104.raw);
+
+		/* there is at least one more byte, otherwise we wouldn't be here */
+		buf[1] = r104.tw_sm_c_104.data2_reg;
+		if (len > 1) buf[2] = r104.tw_sm_c_104.data3_reg;
+		if (len > 2) buf[3] = r104.tw_sm_c_104.data4_reg;
+	}
+	return 0;
+}
+
+static int flexcop_i2c_write4(struct flexcop_device *fc,
+		flexcop_ibi_value r100, u8 *buf)
+{
+	flexcop_ibi_value r104;
+	int len = r100.tw_sm_c_100.total_bytes; /* remember total_bytes is buflen-1 */
+	r104.raw = 0;
+
+	/* there is at least one byte, otherwise we wouldn't be here */
+	r100.tw_sm_c_100.data1_reg = buf[0];
+	r104.tw_sm_c_104.data2_reg = len > 0 ? buf[1] : 0;
+	r104.tw_sm_c_104.data3_reg = len > 1 ? buf[2] : 0;
+	r104.tw_sm_c_104.data4_reg = len > 2 ? buf[3] : 0;
+
+	deb_i2c("write: r100: %08x, r104: %08x\n", r100.raw, r104.raw);
+
+	/* write the additional i2c data before doing the actual i2c operation */
+	fc->write_ibi_reg(fc, tw_sm_c_104, r104);
+	return flexcop_i2c_operation(fc, &r100);
+}
+
+int flexcop_i2c_request(struct flexcop_i2c_adapter *i2c,
+			flexcop_access_op_t op, u8 chipaddr,
+			u8 start_addr, u8 *buf, u16 size)
+{
+	int ret;
+	int len = size;
+	u8 *p;
+	u8 addr = start_addr;
+
+	u16 bytes_to_transfer;
+	flexcop_ibi_value r100;
+
+	deb_i2c("port %d %s(%02x): register %02x, size: %d\n",
+		i2c->port,
+		op == FC_READ ? "rd" : "wr",
+		chipaddr, start_addr, size);
+	r100.raw = 0;
+	r100.tw_sm_c_100.chipaddr = chipaddr;
+	r100.tw_sm_c_100.twoWS_rw = op;
+	r100.tw_sm_c_100.twoWS_port_reg = i2c->port;
+
+	/* in that case addr is the only value ->
+	 * we write it twice as baseaddr and val0
+	 * BBTI is doing it like that for ISL6421 at least */
+	if (i2c->no_base_addr && len == 0 && op == FC_WRITE) {
+		buf = &start_addr;
+		len = 1;
+	}
+
+	p = buf;
+
+	while (len != 0) {
+		bytes_to_transfer = len > 4 ? 4 : len;
+
+		r100.tw_sm_c_100.total_bytes = bytes_to_transfer - 1;
+		r100.tw_sm_c_100.baseaddr = addr;
+
+		if (op == FC_READ)
+			ret = flexcop_i2c_read4(i2c, r100, p);
+		else
+			ret = flexcop_i2c_write4(i2c->fc, r100, p);
+
+		if (ret < 0)
+			return ret;
+
+		p  += bytes_to_transfer;
+		addr += bytes_to_transfer;
+		len  -= bytes_to_transfer;
+	}
+	deb_i2c_dump("port %d %s(%02x): register %02x: %*ph\n",
+		i2c->port,
+		op == FC_READ ? "rd" : "wr",
+		chipaddr, start_addr, size, buf);
+
+	return 0;
+}
+/* exported for PCI i2c */
+EXPORT_SYMBOL(flexcop_i2c_request);
+
+/* master xfer callback for demodulator */
+static int flexcop_master_xfer(struct i2c_adapter *i2c_adap,
+		struct i2c_msg msgs[], int num)
+{
+	struct flexcop_i2c_adapter *i2c = i2c_get_adapdata(i2c_adap);
+	int i, ret = 0;
+
+	/* Some drivers use 1 byte or 0 byte reads as probes, which this
+	 * driver doesn't support.  These probes will always fail, so this
+	 * hack makes them always succeed.  If one knew how, it would of
+	 * course be better to actually do the read.  */
+	if (num == 1 && msgs[0].flags == I2C_M_RD && msgs[0].len <= 1)
+		return 1;
+
+	if (mutex_lock_interruptible(&i2c->fc->i2c_mutex))
+		return -ERESTARTSYS;
+
+	for (i = 0; i < num; i++) {
+		/* reading */
+		if (i+1 < num && (msgs[i+1].flags == I2C_M_RD)) {
+			ret = i2c->fc->i2c_request(i2c, FC_READ, msgs[i].addr,
+					msgs[i].buf[0], msgs[i+1].buf,
+					msgs[i+1].len);
+			i++; /* skip the following message */
+		} else /* writing */
+			ret = i2c->fc->i2c_request(i2c, FC_WRITE, msgs[i].addr,
+					msgs[i].buf[0], &msgs[i].buf[1],
+					msgs[i].len - 1);
+		if (ret < 0) {
+			deb_i2c("i2c master_xfer failed");
+			break;
+		}
+	}
+
+	mutex_unlock(&i2c->fc->i2c_mutex);
+
+	if (ret == 0)
+		ret = num;
+	return ret;
+}
+
+static u32 flexcop_i2c_func(struct i2c_adapter *adapter)
+{
+	return I2C_FUNC_I2C;
+}
+
+static struct i2c_algorithm flexcop_algo = {
+	.master_xfer	= flexcop_master_xfer,
+	.functionality	= flexcop_i2c_func,
+};
+
+int flexcop_i2c_init(struct flexcop_device *fc)
+{
+	int ret;
+	mutex_init(&fc->i2c_mutex);
+
+	fc->fc_i2c_adap[0].fc = fc;
+	fc->fc_i2c_adap[1].fc = fc;
+	fc->fc_i2c_adap[2].fc = fc;
+	fc->fc_i2c_adap[0].port = FC_I2C_PORT_DEMOD;
+	fc->fc_i2c_adap[1].port = FC_I2C_PORT_EEPROM;
+	fc->fc_i2c_adap[2].port = FC_I2C_PORT_TUNER;
+
+	strscpy(fc->fc_i2c_adap[0].i2c_adap.name, "B2C2 FlexCop I2C to demod",
+		sizeof(fc->fc_i2c_adap[0].i2c_adap.name));
+	strscpy(fc->fc_i2c_adap[1].i2c_adap.name, "B2C2 FlexCop I2C to eeprom",
+		sizeof(fc->fc_i2c_adap[1].i2c_adap.name));
+	strscpy(fc->fc_i2c_adap[2].i2c_adap.name, "B2C2 FlexCop I2C to tuner",
+		sizeof(fc->fc_i2c_adap[2].i2c_adap.name));
+
+	i2c_set_adapdata(&fc->fc_i2c_adap[0].i2c_adap, &fc->fc_i2c_adap[0]);
+	i2c_set_adapdata(&fc->fc_i2c_adap[1].i2c_adap, &fc->fc_i2c_adap[1]);
+	i2c_set_adapdata(&fc->fc_i2c_adap[2].i2c_adap, &fc->fc_i2c_adap[2]);
+
+	fc->fc_i2c_adap[0].i2c_adap.algo =
+		fc->fc_i2c_adap[1].i2c_adap.algo =
+		fc->fc_i2c_adap[2].i2c_adap.algo = &flexcop_algo;
+	fc->fc_i2c_adap[0].i2c_adap.algo_data =
+		fc->fc_i2c_adap[1].i2c_adap.algo_data =
+		fc->fc_i2c_adap[2].i2c_adap.algo_data = NULL;
+	fc->fc_i2c_adap[0].i2c_adap.dev.parent =
+		fc->fc_i2c_adap[1].i2c_adap.dev.parent =
+		fc->fc_i2c_adap[2].i2c_adap.dev.parent = fc->dev;
+
+	ret = i2c_add_adapter(&fc->fc_i2c_adap[0].i2c_adap);
+	if (ret < 0)
+		return ret;
+
+	ret = i2c_add_adapter(&fc->fc_i2c_adap[1].i2c_adap);
+	if (ret < 0)
+		goto adap_1_failed;
+
+	ret = i2c_add_adapter(&fc->fc_i2c_adap[2].i2c_adap);
+	if (ret < 0)
+		goto adap_2_failed;
+
+	fc->init_state |= FC_STATE_I2C_INIT;
+	return 0;
+
+adap_2_failed:
+	i2c_del_adapter(&fc->fc_i2c_adap[1].i2c_adap);
+adap_1_failed:
+	i2c_del_adapter(&fc->fc_i2c_adap[0].i2c_adap);
+	return ret;
+}
+
+void flexcop_i2c_exit(struct flexcop_device *fc)
+{
+	if (fc->init_state & FC_STATE_I2C_INIT) {
+		i2c_del_adapter(&fc->fc_i2c_adap[2].i2c_adap);
+		i2c_del_adapter(&fc->fc_i2c_adap[1].i2c_adap);
+		i2c_del_adapter(&fc->fc_i2c_adap[0].i2c_adap);
+	}
+	fc->init_state &= ~FC_STATE_I2C_INIT;
+}