[PATCH v5 1/2] i3c: Drop support for I2C 10 bit addresing

Przemyslaw Gaj
2019-04-16T07:32:11Z

This patch dropps support for I2C devices with 10 bit addressing. When I2C
device with 10 bit address is defined in DT, I3C master registration fails.

Address space for I2C devices has been reduced and ->i2c_funcs() hook has been
removed.

Because this patch series dropped support for 10 bit I2C devices, support is
also dropped in Cadence I3C master driver and Synopsys DesignWare I3C master
driver.

Signed-off-by: Przemyslaw Gaj <pgaj@cadence.com>

---

Main changes between v4 and v5 are:
- Merge HC driver changes into this patch to get rid of NULL pointer
dereference after applying first two patches

Main changes between v3 and v4 are:
- Add i3c_master_i2c_funcs() which reflects current I2C devices functionality.

Main changes between v2 and v3 are:
- Remove i2c_funcs() hook.
- Reduce address space for I2C devices.

Main changes between v1 and v2 are:
- Add error message when registering I2C device with 10 bit address.
---
drivers/i3c/master.c | 21 ++++++++++++++-------
drivers/i3c/master/dw-i3c-master.c | 6 ------
drivers/i3c/master/i3c-master-cdns.c | 10 +---------
include/linux/i3c/master.h | 5 +----
4 files changed, 16 insertions(+), 26 deletions(-)

diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c
index 2dc628d..8800514 100644
--- a/drivers/i3c/master.c
+++ b/drivers/i3c/master.c
@@ -1962,6 +1962,16 @@ of_i3c_master_add_i2c_boardinfo(struct i3c_master_controller *master,
if (ret)
return ret;

+ /*
+ * The I3C Specification does not clearly say I2C devices with 10-bit
+ * address are supported. These devices can't be passed properly through
+ * DEFSLVS command.
+ */
+ if (boardinfo->base.flags & I2C_CLIENT_TEN) {
+ dev_err(&master->dev, "I2C device with 10 bit address not supported.");
+ return -ENOTSUPP;
+ }
+
/* LVR is encoded in reg[2]. */
boardinfo->lvr = reg[2];

@@ -2111,16 +2121,14 @@ static int i3c_master_i2c_adapter_xfer(struct i2c_adapter *adap,
return ret ? ret : nxfers;
}

-static u32 i3c_master_i2c_functionalities(struct i2c_adapter *adap)
+static u32 i3c_master_i2c_funcs(struct i2c_adapter *adapter)
{
- struct i3c_master_controller *master = i2c_adapter_to_i3c_master(adap);
-
- return master->ops->i2c_funcs(master);
+ return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_I2C;
}

static const struct i2c_algorithm i3c_master_i2c_algo = {
.master_xfer = i3c_master_i2c_adapter_xfer,
- .functionality = i3c_master_i2c_functionalities,
+ .functionality = i3c_master_i2c_funcs,
};

static int i3c_master_i2c_adapter_init(struct i3c_master_controller *master)
@@ -2379,8 +2387,7 @@ EXPORT_SYMBOL_GPL(i3c_generic_ibi_recycle_slot);
static int i3c_master_check_ops(const struct i3c_master_controller_ops *ops)
{
if (!ops || !ops->bus_init || !ops->priv_xfers ||
- !ops->send_ccc_cmd || !ops->do_daa || !ops->i2c_xfers ||
- !ops->i2c_funcs)
+ !ops->send_ccc_cmd || !ops->do_daa || !ops->i2c_xfers)
return -EINVAL;

if (ops->request_ibi &&
diff --git a/drivers/i3c/master/dw-i3c-master.c b/drivers/i3c/master/dw-i3c-master.c
index bb03079..9934a12 100644
--- a/drivers/i3c/master/dw-i3c-master.c
+++ b/drivers/i3c/master/dw-i3c-master.c
@@ -1069,11 +1069,6 @@ static void dw_i3c_master_detach_i2c_dev(struct i2c_dev_desc *dev)
kfree(data);
}

-static u32 dw_i3c_master_i2c_funcs(struct i3c_master_controller *m)
-{
- return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
-}
-
static irqreturn_t dw_i3c_master_irq_handler(int irq, void *dev_id)
{
struct dw_i3c_master *master = dev_id;
@@ -1108,7 +1103,6 @@ static const struct i3c_master_controller_ops dw_mipi_i3c_ops = {
.attach_i2c_dev = dw_i3c_master_attach_i2c_dev,
.detach_i2c_dev = dw_i3c_master_detach_i2c_dev,
.i2c_xfers = dw_i3c_master_i2c_xfers,
- .i2c_funcs = dw_i3c_master_i2c_funcs,
};

static int dw_i3c_probe(struct platform_device *pdev)
diff --git a/drivers/i3c/master/i3c-master-cdns.c b/drivers/i3c/master/i3c-master-cdns.c
index 8889a4f..237f24a 100644
--- a/drivers/i3c/master/i3c-master-cdns.c
+++ b/drivers/i3c/master/i3c-master-cdns.c
@@ -864,11 +864,6 @@ static int cdns_i3c_master_i2c_xfers(struct i2c_dev_desc *dev,
return ret;
}

-static u32 cdns_i3c_master_i2c_funcs(struct i3c_master_controller *m)
-{
- return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_I2C | I2C_FUNC_10BIT_ADDR;
-}
-
struct cdns_i3c_i2c_dev_data {
u16 id;
s16 ibi;
@@ -1010,9 +1005,7 @@ static int cdns_i3c_master_attach_i2c_dev(struct i2c_dev_desc *dev)
master->free_rr_slots &= ~BIT(slot);
i2c_dev_set_master_data(dev, data);

- writel(prepare_rr0_dev_address(dev->boardinfo->base.addr) |
- (dev->boardinfo->base.flags & I2C_CLIENT_TEN ?
- DEV_ID_RR0_LVR_EXT_ADDR : 0),
+ writel(prepare_rr0_dev_address(dev->boardinfo->base.addr),
master->regs + DEV_ID_RR0(data->id));
writel(dev->boardinfo->lvr, master->regs + DEV_ID_RR2(data->id));
writel(readl(master->regs + DEVS_CTRL) |
@@ -1518,7 +1511,6 @@ static const struct i3c_master_controller_ops cdns_i3c_master_ops = {
.send_ccc_cmd = cdns_i3c_master_send_ccc_cmd,
.priv_xfers = cdns_i3c_master_priv_xfers,
.i2c_xfers = cdns_i3c_master_i2c_xfers,
- .i2c_funcs = cdns_i3c_master_i2c_funcs,
.enable_ibi = cdns_i3c_master_enable_ibi,
.disable_ibi = cdns_i3c_master_disable_ibi,
.request_ibi = cdns_i3c_master_request_ibi,
diff --git a/include/linux/i3c/master.h b/include/linux/i3c/master.h
index f13fd8b..eca8337 100644
--- a/include/linux/i3c/master.h
+++ b/include/linux/i3c/master.h
@@ -48,7 +48,7 @@ struct i3c_i2c_dev_desc {
#define I3C_LVR_I2C_INDEX(x) ((x) << 5)
#define I3C_LVR_I2C_FM_MODE BIT(4)

-#define I2C_MAX_ADDR GENMASK(9, 0)
+#define I2C_MAX_ADDR GENMASK(6, 0)

/**
* struct i2c_dev_boardinfo - I2C device board information
@@ -390,8 +390,6 @@ struct i3c_bus {
* and i2c_put_dma_safe_msg_buf() helpers provided by the I2C
* framework.
* This method is mandatory.
- * @i2c_funcs: expose the supported I2C functionalities.
- * This method is mandatory.
* @request_ibi: attach an IBI handler to an I3C device. This implies defining
* an IBI handler and the constraints of the IBI (maximum payload
* length and number of pre-allocated slots).
@@ -437,7 +435,6 @@ struct i3c_master_controller_ops {
void (*detach_i2c_dev)(struct i2c_dev_desc *dev);
int (*i2c_xfers)(struct i2c_dev_desc *dev,
const struct i2c_msg *xfers, int nxfers);
- u32 (*i2c_funcs)(struct i3c_master_controller *master);
int (*request_ibi)(struct i3c_dev_desc *dev,
const struct i3c_ibi_setup *req);
void (*free_ibi)(struct i3c_dev_desc *dev);