| Message ID | 20210809063645.2289988-5-xiaoning.wang@nxp.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 01830f8bd8e5696ae5efd3daa81e4328e60a0668 |
| Headers | show |
| Series | i3c: master: svc: some bug fixes and add runtime pm support | expand |
Hi Clark, Just a few nitpicks. Clark Wang <xiaoning.wang@nxp.com> wrote on Mon, 9 Aug 2021 14:36:41 +0800: > When i3c controller reads data from slave device, slave device can stop > returning data with an ACK after any byte. > Add this support for svc i3c controller. Otherwise, it will go TIMEOUT "it will timeout when the slave..." > error path when the slave device ends the read operation early. > > Signed-off-by: Clark Wang <xiaoning.wang@nxp.com> > Reviewed-by: Jun Li <jun.li@nxp.com> > --- > V4 changes: > - Only use COMPLETE flag in the read function. > - Add a reset before each transfer. > V2/V3: No change. > --- > drivers/i3c/master/svc-i3c-master.c | 56 ++++++++++++++++++++--------- > 1 file changed, 39 insertions(+), 17 deletions(-) > > diff --git a/drivers/i3c/master/svc-i3c-master.c b/drivers/i3c/master/svc-i3c-master.c > index 4e69c691253d..e767f307db2d 100644 > --- a/drivers/i3c/master/svc-i3c-master.c > +++ b/drivers/i3c/master/svc-i3c-master.c > @@ -896,27 +896,35 @@ static int svc_i3c_master_do_daa(struct i3c_master_controller *m) > static int svc_i3c_master_read(struct svc_i3c_master *master, > u8 *in, unsigned int len) > { > - int offset = 0, i, ret; > - u32 mdctrl; > + int offset = 0, i; > + u32 mdctrl, mstatus; > + bool completed = false; > + unsigned int count; > + unsigned long start = jiffies; > > - while (offset < len) { > - unsigned int count; > + while (!completed) { > + mstatus = readl(master->regs + SVC_I3C_MSTATUS); > + if (SVC_I3C_MSTATUS_COMPLETE(mstatus) != 0) > + completed = true; > > - ret = readl_poll_timeout(master->regs + SVC_I3C_MDATACTRL, > - mdctrl, > - !(mdctrl & SVC_I3C_MDATACTRL_RXEMPTY), > - 0, 1000); > - if (ret) > - return ret; > + if (time_after(jiffies, start + msecs_to_jiffies(1000))) { > + dev_dbg(master->dev, "<%s> timeout\n", __func__); Can you get rid of this <%s>/__func__ parameter and just tell that we got a read timeout? > + return -ETIMEDOUT; > + } > > + mdctrl = readl(master->regs + SVC_I3C_MDATACTRL); > count = SVC_I3C_MDATACTRL_RXCOUNT(mdctrl); > + if (offset + count > len) { > + dev_err(master->dev, "<%s> recv len too long!\n", > + __func__); > + return -EINVAL; > + } And is this something theoretical or a real error that can happen? If you think this is really needed, please keep the same dev_err() formatting as in the other places in this driver. > for (i = 0; i < count; i++) > in[offset + i] = readl(master->regs + SVC_I3C_MRDATAB); > - Please keep that space > offset += count; > } > > - return 0; > + return offset; > } > > static int svc_i3c_master_write(struct svc_i3c_master *master, > @@ -949,7 +957,7 @@ static int svc_i3c_master_write(struct svc_i3c_master *master, > static int svc_i3c_master_xfer(struct svc_i3c_master *master, > bool rnw, unsigned int xfer_type, u8 addr, > u8 *in, const u8 *out, unsigned int xfer_len, > - unsigned int read_len, bool continued) > + unsigned int *read_len, bool continued) > { > u32 reg; > int ret; > @@ -959,7 +967,7 @@ static int svc_i3c_master_xfer(struct svc_i3c_master *master, > SVC_I3C_MCTRL_IBIRESP_NACK | > SVC_I3C_MCTRL_DIR(rnw) | > SVC_I3C_MCTRL_ADDR(addr) | > - SVC_I3C_MCTRL_RDTERM(read_len), > + SVC_I3C_MCTRL_RDTERM(*read_len), > master->regs + SVC_I3C_MCTRL); > > ret = readl_poll_timeout(master->regs + SVC_I3C_MSTATUS, reg, > @@ -971,17 +979,25 @@ static int svc_i3c_master_xfer(struct svc_i3c_master *master, > ret = svc_i3c_master_read(master, in, xfer_len); > else > ret = svc_i3c_master_write(master, out, xfer_len); > - if (ret) > + if (ret < 0) > goto emit_stop; Space? > + if (rnw) > + *read_len = ret; > > ret = readl_poll_timeout(master->regs + SVC_I3C_MSTATUS, reg, > SVC_I3C_MSTATUS_COMPLETE(reg), 0, 1000); > if (ret) > goto emit_stop; Space? > + writel(SVC_I3C_MINT_COMPLETE, master->regs + SVC_I3C_MSTATUS); > > - if (!continued) > + if (!continued) { > svc_i3c_master_emit_stop(master); > > + /* Wait idle if stop is sent. */ > + readl_poll_timeout(master->regs + SVC_I3C_MSTATUS, reg, > + !SVC_I3C_MSTATUS_STATE(reg), 0, 1000); Please use _MSTATUS_STATE_IDLE() for more clarity. If this wait loop is really needed, better adding it to _master_emit_stop()? (in another patch) > + } > + > return 0; > > emit_stop: > @@ -1039,12 +1055,15 @@ static void svc_i3c_master_start_xfer_locked(struct svc_i3c_master *master) > if (!xfer) > return; > > + svc_i3c_master_clear_merrwarn(master); > + svc_i3c_master_flush_fifo(master); > + > for (i = 0; i < xfer->ncmds; i++) { > struct svc_i3c_cmd *cmd = &xfer->cmds[i]; > > ret = svc_i3c_master_xfer(master, cmd->rnw, xfer->type, > cmd->addr, cmd->in, cmd->out, > - cmd->len, cmd->read_len, > + cmd->len, &cmd->read_len, > cmd->continued); > if (ret) > break; > @@ -1173,6 +1192,9 @@ static int svc_i3c_master_send_direct_ccc_cmd(struct svc_i3c_master *master, > if (!wait_for_completion_timeout(&xfer->comp, msecs_to_jiffies(1000))) > svc_i3c_master_dequeue_xfer(master, xfer); > > + if (cmd->read_len != xfer_len) > + ccc->dests[0].payload.len = cmd->read_len; > + > ret = xfer->ret; > svc_i3c_master_free_xfer(xfer); > Thanks, Miquèl
diff --git a/drivers/i3c/master/svc-i3c-master.c b/drivers/i3c/master/svc-i3c-master.c index 4e69c691253d..e767f307db2d 100644 --- a/drivers/i3c/master/svc-i3c-master.c +++ b/drivers/i3c/master/svc-i3c-master.c @@ -896,27 +896,35 @@ static int svc_i3c_master_do_daa(struct i3c_master_controller *m) static int svc_i3c_master_read(struct svc_i3c_master *master, u8 *in, unsigned int len) { - int offset = 0, i, ret; - u32 mdctrl; + int offset = 0, i; + u32 mdctrl, mstatus; + bool completed = false; + unsigned int count; + unsigned long start = jiffies; - while (offset < len) { - unsigned int count; + while (!completed) { + mstatus = readl(master->regs + SVC_I3C_MSTATUS); + if (SVC_I3C_MSTATUS_COMPLETE(mstatus) != 0) + completed = true; - ret = readl_poll_timeout(master->regs + SVC_I3C_MDATACTRL, - mdctrl, - !(mdctrl & SVC_I3C_MDATACTRL_RXEMPTY), - 0, 1000); - if (ret) - return ret; + if (time_after(jiffies, start + msecs_to_jiffies(1000))) { + dev_dbg(master->dev, "<%s> timeout\n", __func__); + return -ETIMEDOUT; + } + mdctrl = readl(master->regs + SVC_I3C_MDATACTRL); count = SVC_I3C_MDATACTRL_RXCOUNT(mdctrl); + if (offset + count > len) { + dev_err(master->dev, "<%s> recv len too long!\n", + __func__); + return -EINVAL; + } for (i = 0; i < count; i++) in[offset + i] = readl(master->regs + SVC_I3C_MRDATAB); - offset += count; } - return 0; + return offset; } static int svc_i3c_master_write(struct svc_i3c_master *master, @@ -949,7 +957,7 @@ static int svc_i3c_master_write(struct svc_i3c_master *master, static int svc_i3c_master_xfer(struct svc_i3c_master *master, bool rnw, unsigned int xfer_type, u8 addr, u8 *in, const u8 *out, unsigned int xfer_len, - unsigned int read_len, bool continued) + unsigned int *read_len, bool continued) { u32 reg; int ret; @@ -959,7 +967,7 @@ static int svc_i3c_master_xfer(struct svc_i3c_master *master, SVC_I3C_MCTRL_IBIRESP_NACK | SVC_I3C_MCTRL_DIR(rnw) | SVC_I3C_MCTRL_ADDR(addr) | - SVC_I3C_MCTRL_RDTERM(read_len), + SVC_I3C_MCTRL_RDTERM(*read_len), master->regs + SVC_I3C_MCTRL); ret = readl_poll_timeout(master->regs + SVC_I3C_MSTATUS, reg, @@ -971,17 +979,25 @@ static int svc_i3c_master_xfer(struct svc_i3c_master *master, ret = svc_i3c_master_read(master, in, xfer_len); else ret = svc_i3c_master_write(master, out, xfer_len); - if (ret) + if (ret < 0) goto emit_stop; + if (rnw) + *read_len = ret; ret = readl_poll_timeout(master->regs + SVC_I3C_MSTATUS, reg, SVC_I3C_MSTATUS_COMPLETE(reg), 0, 1000); if (ret) goto emit_stop; + writel(SVC_I3C_MINT_COMPLETE, master->regs + SVC_I3C_MSTATUS); - if (!continued) + if (!continued) { svc_i3c_master_emit_stop(master); + /* Wait idle if stop is sent. */ + readl_poll_timeout(master->regs + SVC_I3C_MSTATUS, reg, + !SVC_I3C_MSTATUS_STATE(reg), 0, 1000); + } + return 0; emit_stop: @@ -1039,12 +1055,15 @@ static void svc_i3c_master_start_xfer_locked(struct svc_i3c_master *master) if (!xfer) return; + svc_i3c_master_clear_merrwarn(master); + svc_i3c_master_flush_fifo(master); + for (i = 0; i < xfer->ncmds; i++) { struct svc_i3c_cmd *cmd = &xfer->cmds[i]; ret = svc_i3c_master_xfer(master, cmd->rnw, xfer->type, cmd->addr, cmd->in, cmd->out, - cmd->len, cmd->read_len, + cmd->len, &cmd->read_len, cmd->continued); if (ret) break; @@ -1173,6 +1192,9 @@ static int svc_i3c_master_send_direct_ccc_cmd(struct svc_i3c_master *master, if (!wait_for_completion_timeout(&xfer->comp, msecs_to_jiffies(1000))) svc_i3c_master_dequeue_xfer(master, xfer); + if (cmd->read_len != xfer_len) + ccc->dests[0].payload.len = cmd->read_len; + ret = xfer->ret; svc_i3c_master_free_xfer(xfer);