On Fri, Oct 11, 2024 at 05:47:57PM +0530, Mukesh Kumar Savaliya wrote: Your recipients list is broken. Please check go/upstream and adopt b4 to help avoid such mistakes. > pm_runtime_get_sync() function fails during PM early resume and returning > -EACCES because runtime PM for the device is disabled at the early stage > causing i2c transfer to fail. Make changes to serve transfer with forced > resume. > > Few i2c clients like PCI OR touch may request i2c transfers during early > resume stage. In order to serve transfer request do : > This problem description is too generic. I am not aware of any use case upstream where PCI or touch might need to perform i2c transfers during early resume; your commit message should educate me. > 1. Register interrupt with IRQF_EARLY_RESUME and IRQF_NO_SUSPEND flags > to avoid timeout of transfer when IRQ is not enabled during early stage. > 2. Do force resume if pm_runtime_get_sync() is failing after system > suspend when runtime PM is not enabled. > 3. Increment power usage count after forced resume to balance > it against regular runtime suspend. > Please avoid the bullet list form technical description of your patch. > Co-developed-by: Viken Dadhaniya <quic_vdadhani@xxxxxxxxxxx> > Signed-off-by: Viken Dadhaniya <quic_vdadhani@xxxxxxxxxxx> > Signed-off-by: Mukesh Kumar Savaliya <quic_msavaliy@xxxxxxxxxxx> > --- > v1 -> v2: > > - Changed gi2c->se.dev to dev during dev_dbg() calls. > - Addressed review comments from Andi and Bjorn. That's nice, but spell out the changes you're doing so that reviewers now what you did. > - Returned 0 instead garbage inside geni_i2c_force_resume(). > - Added comments explaining forced resume transfer when runtime PM > remains disabled. > > V1 link: https://patches.linaro.org/project/linux-i2c/patch/20240328123743.1713696-1-quic_msavaliy@xxxxxxxxxxx/ > --- > --- > drivers/i2c/busses/i2c-qcom-geni.c | 61 +++++++++++++++++++++++++----- > 1 file changed, 51 insertions(+), 10 deletions(-) > > diff --git a/drivers/i2c/busses/i2c-qcom-geni.c b/drivers/i2c/busses/i2c-qcom-geni.c > index 212336f724a6..e1207f1a3de3 100644 > --- a/drivers/i2c/busses/i2c-qcom-geni.c > +++ b/drivers/i2c/busses/i2c-qcom-geni.c > @@ -134,6 +134,8 @@ struct geni_i2c_clk_fld { > u8 t_cycle_cnt; > }; > > +static int geni_i2c_runtime_resume(struct device *dev); > + > /* > * Hardware uses the underlying formula to calculate time periods of > * SCL clock cycle. Firmware uses some additional cycles excluded from the > @@ -675,22 +677,49 @@ static int geni_i2c_fifo_xfer(struct geni_i2c_dev *gi2c, > return num; > } > > +static int geni_i2c_force_resume(struct geni_i2c_dev *gi2c) > +{ > + struct device *dev = gi2c->se.dev; > + int ret; > + > + ret = geni_i2c_runtime_resume(dev); Wouldn't pm_runtime_force_resume() help you do what you're looking for? > + if (ret) { > + dev_err(gi2c->se.dev, "Failed to enable SE resources: %d\n", ret); > + pm_runtime_put_noidle(dev); > + pm_runtime_set_suspended(dev); > + return ret; > + } > + pm_runtime_get_noresume(dev); > + pm_runtime_set_active(dev); > + return 0; > +} > + > static int geni_i2c_xfer(struct i2c_adapter *adap, > struct i2c_msg msgs[], > int num) > { > struct geni_i2c_dev *gi2c = i2c_get_adapdata(adap); > + struct device *dev = gi2c->se.dev; > int ret; > > gi2c->err = 0; > reinit_completion(&gi2c->done); > - ret = pm_runtime_get_sync(gi2c->se.dev); > - if (ret < 0) { > - dev_err(gi2c->se.dev, "error turning SE resources:%d\n", ret); > - pm_runtime_put_noidle(gi2c->se.dev); > - /* Set device in suspended since resume failed */ > - pm_runtime_set_suspended(gi2c->se.dev); > - return ret; > + > + /* Serve I2C transfer by forced resume whether Runtime PM is enbled or not */ > + if (!pm_runtime_enabled(dev) && gi2c->suspended) { > + dev_dbg(dev, "Runtime PM is disabled hence force resume, pm_usage_count: %d\n", > + atomic_read(&dev->power.usage_count)); > + ret = geni_i2c_force_resume(gi2c); > + if (ret) > + return ret; > + } else { > + ret = pm_runtime_get_sync(dev); > + if (ret == -EACCES && gi2c->suspended) { > + dev_dbg(dev, "pm_runtime_get_sync() failed-%d, force resume\n", ret); > + ret = geni_i2c_force_resume(gi2c); > + if (ret) > + return ret; > + } > } > > qcom_geni_i2c_conf(gi2c); > @@ -700,8 +729,19 @@ static int geni_i2c_xfer(struct i2c_adapter *adap, > else > ret = geni_i2c_fifo_xfer(gi2c, msgs, num); > > - pm_runtime_mark_last_busy(gi2c->se.dev); > - pm_runtime_put_autosuspend(gi2c->se.dev); > + /* Does Opposite to Forced Resume when runtime PM was not enabled and served > + * Transfer via forced resume. Please polish this comment. Regards, Bjorn > + */ > + if (!pm_runtime_enabled(dev) && !gi2c->suspended) { > + pm_runtime_put_noidle(dev); > + pm_runtime_set_suspended(dev); > + /* Reset flag same as runtime suspend, next xfer PM can be enabled */ > + gi2c->suspended = 0; > + } else { > + pm_runtime_mark_last_busy(gi2c->se.dev); > + pm_runtime_put_autosuspend(gi2c->se.dev); > + } > + > gi2c->cur = NULL; > gi2c->err = 0; > return ret; > @@ -818,7 +858,8 @@ static int geni_i2c_probe(struct platform_device *pdev) > init_completion(&gi2c->done); > spin_lock_init(&gi2c->lock); > platform_set_drvdata(pdev, gi2c); > - ret = devm_request_irq(dev, gi2c->irq, geni_i2c_irq, IRQF_NO_AUTOEN, > + ret = devm_request_irq(dev, gi2c->irq, geni_i2c_irq, > + IRQF_NO_AUTOEN | IRQF_EARLY_RESUME | IRQF_NO_SUSPEND, > dev_name(dev), gi2c); > if (ret) { > dev_err(dev, "Request_irq failed:%d: err:%d\n", > -- > 2.25.1 >
