Hi,
thanks for the patch.
> >+/* capabilities */
> >+#define I2C_CAPABILITIES (I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | \
> >+ I2C_FUNC_SMBUS_READ_BLOCK_DATA)
I don't see the need for a seperate define.
> >+
> > struct davinci_i2c_dev {
> > struct device *dev;
> > void __iomem *base;
> >@@ -318,7 +322,13 @@ i2c_davinci_xfer_msg(struct i2c_adapter *adap, struct i2c_msg
> >*msg, int stop)
> > davinci_i2c_write_reg(dev, DAVINCI_I2C_SAR_REG, msg->addr);
> >
> > dev->buf = msg->buf;
> >- dev->buf_len = msg->len;
> >+
> >+ /* if first received byte is length, set buf_len = 0xffff as flag */
> >+ if (msg->flags & I2C_M_RECV_LEN)
> >+ dev->buf_len = 0xffff;
a) this magic value should be a define instead of a comment
b) i2c messages easily have a 16 bit range, so 0xffff is a troublesome
choice.
> >+ else
> >+ dev->buf_len = msg->len;
> >+
> > dev->stop = stop;
> >
> > davinci_i2c_write_reg(dev, DAVINCI_I2C_CNT_REG, dev->buf_len); @@ -456,7
> >+466,7 @@ i2c_davinci_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
> >
> > static u32 i2c_davinci_func(struct i2c_adapter *adap) {
> >- return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
> >+ return I2C_CAPABILITIES;
> > }
> >
> > static void terminate_read(struct davinci_i2c_dev *dev) @@ -528,10 +538,32 @@ static
> >irqreturn_t i2c_davinci_isr(int this_irq, void *dev_id)
> >
> > case DAVINCI_I2C_IVR_RDR:
> > if (dev->buf_len) {
> >- *dev->buf++ =
> >- davinci_i2c_read_reg(dev,
> >- DAVINCI_I2C_DRR_REG);
> >+ *dev->buf++ = davinci_i2c_read_reg(dev,
> >+ DAVINCI_I2C_DRR_REG);
> >+ /*
> >+ * check if the first received byte is message
> >+ * length, i.e, I2C_M_RECV_LEN
> >+ */
> >+ if (dev->buf_len == 0xffff)
> >+ dev->buf_len = *(dev->buf - 1) + 1;
Please rework the code to get rid of the '- 1' and '+ 1'. They look
hackish and make the code less readable.
> >+
> > dev->buf_len--;
> >+ /*
> >+ * send NACK/STOP bits BEFORE last byte is
> >+ * received
> >+ */
> >+ if (dev->buf_len == 1) {
> >+ w = davinci_i2c_read_reg(dev,
> >+ DAVINCI_I2C_MDR_REG);
> >+ w |= DAVINCI_I2C_MDR_NACK;
> >+ davinci_i2c_write_reg(dev,
> >+ DAVINCI_I2C_MDR_REG, w);
> >+
> >+ w |= DAVINCI_I2C_MDR_STP;
> >+ davinci_i2c_write_reg(dev,
> >+ DAVINCI_I2C_MDR_REG, w);
> >+ }
> >+
Looks like an unreleated change to me? Why is this I2C_M_RECV_LEN
specific?
Kind regards,
Wolfram
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