[PATCH] dvb: b2c2/flexcop driver refactoring part 2: add modular Flexcop driver

b2c2/flexcop driver refactoring to support PCI and USB based cards part 2: add
modular Flexcop driver

Signed-off-by: Patrick Boettcher <pb@linuxtv.org>
Signed-off-by: Johannes Stezenbach <js@linuxtv.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 204 insertions, 0 deletions

diff --git a/drivers/media/dvb/b2c2/flexcop-i2c.c b/drivers/media/dvb/b2c2/flexcop-i2c.c
new file mode 100644
index 000000000000..736251f393c2
--- /dev/null
+++ b/drivers/media/dvb/b2c2/flexcop-i2c.c
@@ -0,0 +1,204 @@
+/*
+ * This file is part of linux driver the 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 max_ack_errors)
+{
+        int i,ack_errors = 0;
+        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) {  /* && !r.tw_sm_c_100.working_start */
+                                *r100 = r;
+                                deb_i2c("i2c success\n");
+                                return 0;
+                        }
+                } else {
+                        deb_i2c("suffering from an i2c ack_error\n");
+                        if (++ack_errors >= max_ack_errors)
+                                break;
+
+                        fc->write_ibi_reg(fc, tw_sm_c_100, ibi_zero);
+                        fc->write_ibi_reg(fc, tw_sm_c_100, *r100);
+                }
+        }
+        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_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 */
+                ret;
+
+        if ((ret = flexcop_i2c_operation(fc,&r100,30)) != 0)
+                return ret;
+
+        r104 = fc->read_ibi_reg(fc,tw_sm_c_104);
+
+        deb_i2c("read: r100: %08x, r104: %08x\n",r100.raw,r104.raw);
+
+        /* there is at least one byte, otherwise we wouldn't be here */
+        buf[0] = r100.tw_sm_c_100.data1_reg;
+
+        if (len > 0) 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,&r100,30);
+}
+
+/* master xfer callback for demodulator */
+static int flexcop_master_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg msgs[], int num)
+{
+        struct flexcop_device *fc = i2c_get_adapdata(i2c_adap);
+        int i, ret = 0;
+
+        if (down_interruptible(&fc->i2c_sem))
+                return -ERESTARTSYS;
+
+        /* reading */
+        if (num == 2 &&
+                msgs[0].flags == 0 &&
+                msgs[1].flags == I2C_M_RD &&
+                msgs[0].buf != NULL &&
+                msgs[1].buf != NULL) {
+
+                ret = fc->i2c_request(fc, FC_READ, FC_I2C_PORT_DEMOD, msgs[0].addr, msgs[0].buf[0], msgs[1].buf, msgs[1].len);
+
+        } else for (i = 0; i < num; i++) { /* writing command */
+                if (msgs[i].flags != 0 || msgs[i].buf == NULL || msgs[i].len < 2) {
+                        ret = -EINVAL;
+                        break;
+                }
+
+                ret = fc->i2c_request(fc, FC_WRITE, FC_I2C_PORT_DEMOD, msgs[i].addr, msgs[i].buf[0], &msgs[i].buf[1], msgs[i].len - 1);
+        }
+
+        if (ret < 0)
+                err("i2c master_xfer failed");
+        else
+                ret = num;
+
+        up(&fc->i2c_sem);
+
+        return ret;
+}
+
+int flexcop_i2c_request(struct flexcop_device *fc, flexcop_access_op_t op,
+                flexcop_i2c_port_t port, u8 chipaddr, u8 addr, u8 *buf, u16 len)
+{
+        int ret;
+        u16 bytes_to_transfer;
+        flexcop_ibi_value r100;
+
+        deb_i2c("op = %d\n",op);
+        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 = port;
+
+        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(fc, r100, buf);
+                else
+                        ret = flexcop_i2c_write4(fc,r100, buf);
+
+                if (ret < 0)
+                        return ret;
+
+                buf  += bytes_to_transfer;
+                addr += bytes_to_transfer;
+                len  -= bytes_to_transfer;
+        };
+
+        return 0;
+}
+/* exported for PCI i2c */
+EXPORT_SYMBOL(flexcop_i2c_request);
+
+static u32 flexcop_i2c_func(struct i2c_adapter *adapter)
+{
+        return I2C_FUNC_I2C;
+}
+
+static struct i2c_algorithm flexcop_algo = {
+        .name                   = "FlexCop I2C algorithm",
+        .id                             = I2C_ALGO_BIT,
+        .master_xfer    = flexcop_master_xfer,
+        .functionality  = flexcop_i2c_func,
+};
+
+int flexcop_i2c_init(struct flexcop_device *fc)
+{
+        int ret;
+
+        sema_init(&fc->i2c_sem,1);
+
+        memset(&fc->i2c_adap, 0, sizeof(struct i2c_adapter));
+        strncpy(fc->i2c_adap.name, "B2C2 FlexCop device",I2C_NAME_SIZE);
+
+        i2c_set_adapdata(&fc->i2c_adap,fc);
+
+        fc->i2c_adap.class          = I2C_CLASS_TV_DIGITAL;
+        fc->i2c_adap.algo       = &flexcop_algo;
+        fc->i2c_adap.algo_data  = NULL;
+        fc->i2c_adap.id         = I2C_ALGO_BIT;
+
+        if ((ret = i2c_add_adapter(&fc->i2c_adap)) < 0)
+                return ret;
+
+        fc->init_state |= FC_STATE_I2C_INIT;
+        return 0;
+}
+
+void flexcop_i2c_exit(struct flexcop_device *fc)
+{
+        if (fc->init_state & FC_STATE_I2C_INIT)
+                i2c_del_adapter(&fc->i2c_adap);
+
+        fc->init_state &= ~FC_STATE_I2C_INIT;
+}