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path: root/drivers/media/pci/pt3/pt3_i2c.c
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Diffstat (limited to 'drivers/media/pci/pt3/pt3_i2c.c')
-rw-r--r--drivers/media/pci/pt3/pt3_i2c.c240
1 files changed, 240 insertions, 0 deletions
diff --git a/drivers/media/pci/pt3/pt3_i2c.c b/drivers/media/pci/pt3/pt3_i2c.c
new file mode 100644
index 0000000..ec6a8a2
--- /dev/null
+++ b/drivers/media/pci/pt3/pt3_i2c.c
@@ -0,0 +1,240 @@
+/*
+ * Earthsoft PT3 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.
+ */
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/i2c.h>
+#include <linux/io.h>
+#include <linux/pci.h>
+
+#include "pt3.h"
+
+#define PT3_I2C_BASE 2048
+#define PT3_CMD_ADDR_NORMAL 0
+#define PT3_CMD_ADDR_INIT_DEMOD 4096
+#define PT3_CMD_ADDR_INIT_TUNER (4096 + 2042)
+
+/* masks for I2C status register */
+#define STAT_SEQ_RUNNING 0x1
+#define STAT_SEQ_ERROR 0x6
+#define STAT_NO_SEQ 0x8
+
+#define PT3_I2C_RUN (1 << 16)
+#define PT3_I2C_RESET (1 << 17)
+
+enum ctl_cmd {
+ I_END,
+ I_ADDRESS,
+ I_CLOCK_L,
+ I_CLOCK_H,
+ I_DATA_L,
+ I_DATA_H,
+ I_RESET,
+ I_SLEEP,
+ I_DATA_L_NOP = 0x08,
+ I_DATA_H_NOP = 0x0c,
+ I_DATA_H_READ = 0x0d,
+ I_DATA_H_ACK0 = 0x0e,
+ I_DATA_H_ACK1 = 0x0f,
+};
+
+
+static void cmdbuf_add(struct pt3_i2cbuf *cbuf, enum ctl_cmd cmd)
+{
+ int buf_idx;
+
+ if ((cbuf->num_cmds % 2) == 0)
+ cbuf->tmp = cmd;
+ else {
+ cbuf->tmp |= cmd << 4;
+ buf_idx = cbuf->num_cmds / 2;
+ if (buf_idx < ARRAY_SIZE(cbuf->data))
+ cbuf->data[buf_idx] = cbuf->tmp;
+ }
+ cbuf->num_cmds++;
+}
+
+static void put_end(struct pt3_i2cbuf *cbuf)
+{
+ cmdbuf_add(cbuf, I_END);
+ if (cbuf->num_cmds % 2)
+ cmdbuf_add(cbuf, I_END);
+}
+
+static void put_start(struct pt3_i2cbuf *cbuf)
+{
+ cmdbuf_add(cbuf, I_DATA_H);
+ cmdbuf_add(cbuf, I_CLOCK_H);
+ cmdbuf_add(cbuf, I_DATA_L);
+ cmdbuf_add(cbuf, I_CLOCK_L);
+}
+
+static void put_byte_write(struct pt3_i2cbuf *cbuf, u8 val)
+{
+ u8 mask;
+
+ mask = 0x80;
+ for (mask = 0x80; mask > 0; mask >>= 1)
+ cmdbuf_add(cbuf, (val & mask) ? I_DATA_H_NOP : I_DATA_L_NOP);
+ cmdbuf_add(cbuf, I_DATA_H_ACK0);
+}
+
+static void put_byte_read(struct pt3_i2cbuf *cbuf, u32 size)
+{
+ int i, j;
+
+ for (i = 0; i < size; i++) {
+ for (j = 0; j < 8; j++)
+ cmdbuf_add(cbuf, I_DATA_H_READ);
+ cmdbuf_add(cbuf, (i == size - 1) ? I_DATA_H_NOP : I_DATA_L_NOP);
+ }
+}
+
+static void put_stop(struct pt3_i2cbuf *cbuf)
+{
+ cmdbuf_add(cbuf, I_DATA_L);
+ cmdbuf_add(cbuf, I_CLOCK_H);
+ cmdbuf_add(cbuf, I_DATA_H);
+}
+
+
+/* translates msgs to internal commands for bit-banging */
+static void translate(struct pt3_i2cbuf *cbuf, struct i2c_msg *msgs, int num)
+{
+ int i, j;
+ bool rd;
+
+ cbuf->num_cmds = 0;
+ for (i = 0; i < num; i++) {
+ rd = !!(msgs[i].flags & I2C_M_RD);
+ put_start(cbuf);
+ put_byte_write(cbuf, msgs[i].addr << 1 | rd);
+ if (rd)
+ put_byte_read(cbuf, msgs[i].len);
+ else
+ for (j = 0; j < msgs[i].len; j++)
+ put_byte_write(cbuf, msgs[i].buf[j]);
+ }
+ if (num > 0) {
+ put_stop(cbuf);
+ put_end(cbuf);
+ }
+}
+
+static int wait_i2c_result(struct pt3_board *pt3, u32 *result, int max_wait)
+{
+ int i;
+ u32 v;
+
+ for (i = 0; i < max_wait; i++) {
+ v = ioread32(pt3->regs[0] + REG_I2C_R);
+ if (!(v & STAT_SEQ_RUNNING))
+ break;
+ usleep_range(500, 750);
+ }
+ if (i >= max_wait)
+ return -EIO;
+ if (result)
+ *result = v;
+ return 0;
+}
+
+/* send [pre-]translated i2c msgs stored at addr */
+static int send_i2c_cmd(struct pt3_board *pt3, u32 addr)
+{
+ u32 ret;
+
+ /* make sure that previous transactions had finished */
+ if (wait_i2c_result(pt3, NULL, 50)) {
+ dev_warn(&pt3->pdev->dev, "(%s) prev. transaction stalled\n",
+ __func__);
+ return -EIO;
+ }
+
+ iowrite32(PT3_I2C_RUN | addr, pt3->regs[0] + REG_I2C_W);
+ usleep_range(200, 300);
+ /* wait for the current transaction to finish */
+ if (wait_i2c_result(pt3, &ret, 500) || (ret & STAT_SEQ_ERROR)) {
+ dev_warn(&pt3->pdev->dev, "(%s) failed.\n", __func__);
+ return -EIO;
+ }
+ return 0;
+}
+
+
+/* init commands for each demod are combined into one transaction
+ * and hidden in ROM with the address PT3_CMD_ADDR_INIT_DEMOD.
+ */
+int pt3_init_all_demods(struct pt3_board *pt3)
+{
+ ioread32(pt3->regs[0] + REG_I2C_R);
+ return send_i2c_cmd(pt3, PT3_CMD_ADDR_INIT_DEMOD);
+}
+
+/* init commands for two ISDB-T tuners are hidden in ROM. */
+int pt3_init_all_mxl301rf(struct pt3_board *pt3)
+{
+ usleep_range(1000, 2000);
+ return send_i2c_cmd(pt3, PT3_CMD_ADDR_INIT_TUNER);
+}
+
+void pt3_i2c_reset(struct pt3_board *pt3)
+{
+ iowrite32(PT3_I2C_RESET, pt3->regs[0] + REG_I2C_W);
+}
+
+/*
+ * I2C algorithm
+ */
+int
+pt3_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
+{
+ struct pt3_board *pt3;
+ struct pt3_i2cbuf *cbuf;
+ int i;
+ void __iomem *p;
+
+ pt3 = i2c_get_adapdata(adap);
+ cbuf = pt3->i2c_buf;
+
+ for (i = 0; i < num; i++)
+ if (msgs[i].flags & I2C_M_RECV_LEN) {
+ dev_warn(&pt3->pdev->dev,
+ "(%s) I2C_M_RECV_LEN not supported.\n",
+ __func__);
+ return -EINVAL;
+ }
+
+ translate(cbuf, msgs, num);
+ memcpy_toio(pt3->regs[1] + PT3_I2C_BASE + PT3_CMD_ADDR_NORMAL / 2,
+ cbuf->data, cbuf->num_cmds);
+
+ if (send_i2c_cmd(pt3, PT3_CMD_ADDR_NORMAL) < 0)
+ return -EIO;
+
+ p = pt3->regs[1] + PT3_I2C_BASE;
+ for (i = 0; i < num; i++)
+ if ((msgs[i].flags & I2C_M_RD) && msgs[i].len > 0) {
+ memcpy_fromio(msgs[i].buf, p, msgs[i].len);
+ p += msgs[i].len;
+ }
+
+ return num;
+}
+
+u32 pt3_i2c_functionality(struct i2c_adapter *adap)
+{
+ return I2C_FUNC_I2C;
+}

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