[PATCH 28/57] media: Add ovxxxx_16bit_addr_reg_helpers.h

Hans de Goede
2023-01-23T12:54:41Z

The following drivers under drivers/media/i2c: ov08x40.c, ov13858.c,
ov13b10.c, ov2680.c, ov2685.c, ov2740.c, ov4689.c, ov5670.c,
ov5675.c, ov5695.c, ov8856.c, ov9282.c and ov9734.c,

as well as various "atomisp" sensor drivers in drivers/staging, *all*
use register access helpers with the following function prototypes:

int ovxxxx_read_reg(struct ovxxxx_dev *sensor, u16 reg,
unsigned int len, u32 *val);

int ovxxxx_write_reg(struct ovxxxx_dev *sensor, u16 reg,
unsigned int len, u32 val);

To read/write registers on Omnivision OVxxxx image sensors wich expect
a 16 bit register address in big-endian format and which have 1-3 byte
wide registers, in big-endian format (for the higher width registers).

Add a new ovxxxx_16bit_addr_reg_helpers.h header file with static inline
versions of these register access helpers, so that this code duplication
can be removed.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
include/media/ovxxxx_16bit_addr_reg_helpers.h | 93 +++++++++++++++++++
1 file changed, 93 insertions(+)
create mode 100644 include/media/ovxxxx_16bit_addr_reg_helpers.h

diff --git a/include/media/ovxxxx_16bit_addr_reg_helpers.h b/include/media/ovxxxx_16bit_addr_reg_helpers.h
new file mode 100644
index 000000000000..e2ffee3d797a
--- /dev/null
+++ b/include/media/ovxxxx_16bit_addr_reg_helpers.h
@@ -0,0 +1,93 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * I2C register access helpers for Omnivision OVxxxx image sensors which expect
+ * a 16 bit register address in big-endian format and which have 1-3 byte
+ * wide registers, in big-endian format (for the higher width registers).
+ *
+ * Based on the register helpers from drivers/media/i2c/ov2680.c which is:
+ * Copyright (C) 2018 Linaro Ltd
+ */
+#ifndef __OVXXXX_16BIT_ADDR_REG_HELPERS_H
+#define __OVXXXX_16BIT_ADDR_REG_HELPERS_H
+
+#include <asm/unaligned.h>
+#include <linux/dev_printk.h>
+#include <linux/i2c.h>
+
+static inline int ovxxxx_read_reg(struct i2c_client *client, u16 reg,
+ unsigned int len, u32 *val)
+{
+ struct i2c_msg msgs[2];
+ u8 addr_buf[2] = { reg >> 8, reg & 0xff };
+ u8 data_buf[4] = { 0, };
+ int ret;
+
+ if (len > 4)
+ return -EINVAL;
+
+ msgs[0].addr = client->addr;
+ msgs[0].flags = 0;
+ msgs[0].len = ARRAY_SIZE(addr_buf);
+ msgs[0].buf = addr_buf;
+
+ msgs[1].addr = client->addr;
+ msgs[1].flags = I2C_M_RD;
+ msgs[1].len = len;
+ msgs[1].buf = &data_buf[4 - len];
+
+ ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
+ if (ret != ARRAY_SIZE(msgs)) {
+ dev_err(&client->dev, "read error: reg=0x%4x: %d\n", reg, ret);
+ return -EIO;
+ }
+
+ *val = get_unaligned_be32(data_buf);
+
+ return 0;
+}
+
+#define ovxxxx_read_reg8(s, r, v) ovxxxx_read_reg(s, r, 1, v)
+#define ovxxxx_read_reg16(s, r, v) ovxxxx_read_reg(s, r, 2, v)
+#define ovxxxx_read_reg24(s, r, v) ovxxxx_read_reg(s, r, 3, v)
+
+static inline int ovxxxx_write_reg(struct i2c_client *client, u16 reg,
+ unsigned int len, u32 val)
+{
+ u8 buf[6];
+ int ret;
+
+ if (len > 4)
+ return -EINVAL;
+
+ put_unaligned_be16(reg, buf);
+ put_unaligned_be32(val << (8 * (4 - len)), buf + 2);
+ ret = i2c_master_send(client, buf, len + 2);
+ if (ret != len + 2) {
+ dev_err(&client->dev, "write error: reg=0x%4x: %d\n", reg, ret);
+ return -EIO;
+ }
+
+ return 0;
+}
+
+#define ovxxxx_write_reg8(s, r, v) ovxxxx_write_reg(s, r, 1, v)
+#define ovxxxx_write_reg16(s, r, v) ovxxxx_write_reg(s, r, 2, v)
+#define ovxxxx_write_reg24(s, r, v) ovxxxx_write_reg(s, r, 3, v)
+
+static inline int ovxxxx_mod_reg(struct i2c_client *client, u16 reg, u8 mask, u8 val)
+{
+ u32 readval;
+ int ret;
+
+ ret = ovxxxx_read_reg8(client, reg, &readval);
+ if (ret < 0)
+ return ret;
+
+ readval &= ~mask;
+ val &= mask;
+ val |= readval;
+
+ return ovxxxx_write_reg8(client, reg, val);
+}
+
+#endif
--
2.39.0