From d84eb856c4385c90f4f68594819744b638f77a02 Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Tue, 30 Oct 2012 07:28:52 +0000 Subject: [PATCH] tegra: i2c: Add function to know about current bus Rather than using a variable in various places, add a single function, tegra_i2c_get_bus(), which returns a pointer to information about a bus. This will make it easier to move to the new i2c framework. Signed-off-by: Simon Glass --- drivers/i2c/tegra_i2c.c | 78 ++++++++++++++++++++++++++++++++--------- 1 file changed, 61 insertions(+), 17 deletions(-) diff --git a/drivers/i2c/tegra_i2c.c b/drivers/i2c/tegra_i2c.c index ca71cd3ee4..8fa1cdac02 100644 --- a/drivers/i2c/tegra_i2c.c +++ b/drivers/i2c/tegra_i2c.c @@ -284,7 +284,8 @@ exit: return error; } -static int tegra_i2c_write_data(u32 addr, u8 *data, u32 len) +static int tegra_i2c_write_data(struct i2c_bus *bus, u32 addr, u8 *data, + u32 len) { int error; struct i2c_trans_info trans_info; @@ -295,14 +296,15 @@ static int tegra_i2c_write_data(u32 addr, u8 *data, u32 len) trans_info.num_bytes = len; trans_info.is_10bit_address = 0; - error = send_recv_packets(&i2c_controllers[i2c_bus_num], &trans_info); + error = send_recv_packets(bus, &trans_info); if (error) debug("tegra_i2c_write_data: Error (%d) !!!\n", error); return error; } -static int tegra_i2c_read_data(u32 addr, u8 *data, u32 len) +static int tegra_i2c_read_data(struct i2c_bus *bus, u32 addr, u8 *data, + u32 len) { int error; struct i2c_trans_info trans_info; @@ -313,7 +315,7 @@ static int tegra_i2c_read_data(u32 addr, u8 *data, u32 len) trans_info.num_bytes = len; trans_info.is_10bit_address = 0; - error = send_recv_packets(&i2c_controllers[i2c_bus_num], &trans_info); + error = send_recv_packets(bus, &trans_info); if (error) debug("tegra_i2c_read_data: Error (%d) !!!\n", error); @@ -324,18 +326,48 @@ static int tegra_i2c_read_data(u32 addr, u8 *data, u32 len) #error "Please enable device tree support to use this driver" #endif +/** + * Check that a bus number is valid and return a pointer to it + * + * @param bus_num Bus number to check / return + * @return pointer to bus, if valid, else NULL + */ +static struct i2c_bus *tegra_i2c_get_bus(unsigned int bus_num) +{ + struct i2c_bus *bus; + + if (bus_num >= TEGRA_I2C_NUM_CONTROLLERS) { + debug("%s: Invalid bus number %u\n", __func__, bus_num); + return NULL; + } + bus = &i2c_controllers[bus_num]; + if (!bus->inited) { + debug("%s: Bus %u not available\n", __func__, bus_num); + return NULL; + } + + return bus; +} + unsigned int i2c_get_bus_speed(void) { - return i2c_controllers[i2c_bus_num].speed; + struct i2c_bus *bus; + + bus = tegra_i2c_get_bus(i2c_bus_num); + if (!bus) + return 0; + return bus->speed; } int i2c_set_bus_speed(unsigned int speed) { - struct i2c_bus *i2c_bus; + struct i2c_bus *bus; - i2c_bus = &i2c_controllers[i2c_bus_num]; - i2c_bus->speed = speed; - i2c_init_controller(i2c_bus); + bus = tegra_i2c_get_bus(i2c_bus_num); + if (!bus) + return 0; + bus->speed = speed; + i2c_init_controller(bus); return 0; } @@ -458,7 +490,7 @@ void i2c_init(int speed, int slaveaddr) } /* i2c write version without the register address */ -int i2c_write_data(uchar chip, uchar *buffer, int len) +int i2c_write_data(struct i2c_bus *bus, uchar chip, uchar *buffer, int len) { int rc; @@ -470,7 +502,7 @@ int i2c_write_data(uchar chip, uchar *buffer, int len) debug("\n"); /* Shift 7-bit address over for lower-level i2c functions */ - rc = tegra_i2c_write_data(chip << 1, buffer, len); + rc = tegra_i2c_write_data(bus, chip << 1, buffer, len); if (rc) debug("i2c_write_data(): rc=%d\n", rc); @@ -478,13 +510,13 @@ int i2c_write_data(uchar chip, uchar *buffer, int len) } /* i2c read version without the register address */ -int i2c_read_data(uchar chip, uchar *buffer, int len) +int i2c_read_data(struct i2c_bus *bus, uchar chip, uchar *buffer, int len) { int rc; debug("inside i2c_read_data():\n"); /* Shift 7-bit address over for lower-level i2c functions */ - rc = tegra_i2c_read_data(chip << 1, buffer, len); + rc = tegra_i2c_read_data(bus, chip << 1, buffer, len); if (rc) { debug("i2c_read_data(): rc=%d\n", rc); return rc; @@ -502,12 +534,16 @@ int i2c_read_data(uchar chip, uchar *buffer, int len) /* Probe to see if a chip is present. */ int i2c_probe(uchar chip) { + struct i2c_bus *bus; int rc; uchar reg; debug("i2c_probe: addr=0x%x\n", chip); + bus = tegra_i2c_get_bus(i2c_get_bus_num()); + if (!bus) + return 1; reg = 0; - rc = i2c_write_data(chip, ®, 1); + rc = i2c_write_data(bus, chip, ®, 1); if (rc) { debug("Error probing 0x%x.\n", chip); return 1; @@ -524,11 +560,15 @@ static int i2c_addr_ok(const uint addr, const int alen) /* Read bytes */ int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len) { + struct i2c_bus *bus; uint offset; int i; debug("i2c_read: chip=0x%x, addr=0x%x, len=0x%x\n", chip, addr, len); + bus = tegra_i2c_get_bus(i2c_bus_num); + if (!bus) + return 1; if (!i2c_addr_ok(addr, alen)) { debug("i2c_read: Bad address %x.%d.\n", addr, alen); return 1; @@ -540,13 +580,13 @@ int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len) data[alen - i - 1] = (addr + offset) >> (8 * i); } - if (i2c_write_data(chip, data, alen)) { + if (i2c_write_data(bus, chip, data, alen)) { debug("i2c_read: error sending (0x%x)\n", addr); return 1; } } - if (i2c_read_data(chip, buffer + offset, 1)) { + if (i2c_read_data(bus, chip, buffer + offset, 1)) { debug("i2c_read: error reading (0x%x)\n", addr); return 1; } @@ -558,11 +598,15 @@ int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len) /* Write bytes */ int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len) { + struct i2c_bus *bus; uint offset; int i; debug("i2c_write: chip=0x%x, addr=0x%x, len=0x%x\n", chip, addr, len); + bus = tegra_i2c_get_bus(i2c_bus_num); + if (!bus) + return 1; if (!i2c_addr_ok(addr, alen)) { debug("i2c_write: Bad address %x.%d.\n", addr, alen); return 1; @@ -572,7 +616,7 @@ int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len) for (i = 0; i < alen; i++) data[alen - i - 1] = (addr + offset) >> (8 * i); data[alen] = buffer[offset]; - if (i2c_write_data(chip, data, alen + 1)) { + if (i2c_write_data(bus, chip, data, alen + 1)) { debug("i2c_write: error sending (0x%x)\n", addr); return 1; } -- 2.30.2