On Mon, Jul 22, 2019 at 10:13:56AM +0200, Marc Gonzalez wrote:
> On 21/07/2019 17:02, Ezequiel Garcia wrote:
>
> > On Thu, 2019-07-18 at 15:03 +0200, Marc Gonzalez wrote:
> >
> >> Provide devm variants for automatic resource release on device removal.
> >> Makes error-handling in probe() simpler, thus less error-prone.
> >> Once all resources are devmanaged, remove() is no longer needed.
> >
> > I think it would be better to add this API as part of a series
> > that also uses it.
>
> I have an outstanding RFC for a new driver:
>
> https://patchwork.kernel.org/patch/11040435/
>
> Locally, I've updated the probe function to use the proposed devm functions.
>
> I was mainly hoping to get initial feedback from the maintainers.
> 1) See if they're OK with devm APIs
devm_ has some lifetime issues, wrt to disconnect. However, for a platform
device it is fine.
> 2) See if they're OK with the way I implemented devm APIs
Looks good to me.
> 3) See what's missing to get an Ack
Please submit both this patch and a the driver as a series.
Thanks,
Sean
>
> static int tsif_probe(struct platform_device *pdev)
> {
> int err, virq;
> struct tsif *tsif;
> struct resource *res;
> struct dvb_frontend *fe;
> struct dvb_adapter *adap;
> struct device *dev = &pdev->dev;
> short num = DVB_UNSET;
>
> fe = dvb_get_demod_fe(dev->of_node);
> if (!fe)
> return -ENXIO;
>
> tsif = devm_kzalloc(dev, sizeof(*tsif), GFP_KERNEL);
> if (!tsif)
> return -ENOMEM;
>
> res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "tsif0");
> tsif->base = devm_ioremap_resource(dev, res);
> if (IS_ERR(tsif->base))
> return PTR_ERR(tsif->base);
>
> virq = platform_get_irq_byname(pdev, "tsif0");
> err = devm_request_irq(dev, virq, tsif_isr, IRQF_SHARED, "tsif", tsif);
> if (err)
> return err;
>
> tsif->clk = devm_clk_get(dev, "iface");
> if (IS_ERR(tsif->clk))
> return PTR_ERR(tsif->clk);
>
> err = devm_clk_prepare_enable(dev, tsif->clk);
> if (err)
> return err;
>
> adap = &tsif->adapter;
> err = devm_dvb_register_adapter(dev, adap, "tsif", THIS_MODULE, &num);
> if (err) return err;
>
> /* Not sure the diff between filter and feed? */
> tsif->demux.filternum = 16; /*** Dunno what to put here ***/
> tsif->demux.feednum = 16; /*** Dunno what to put here ***/
> tsif->demux.start_feed = noop;
> tsif->demux.stop_feed = noop;
> err = devm_dvb_dmx_init(dev, &tsif->demux);
> if (err) return err;
>
> /* What relation to dvb_demux.filternum??? */
> /* Do I need this object?? */
> tsif->dmxdev.filternum = 16;
> tsif->dmxdev.demux = &tsif->demux.dmx;
> err = devm_dvb_dmxdev_init(dev, &tsif->dmxdev, adap);
> if (err) return err;
>
> err = devm_dvb_register_frontend(dev, adap, fe);
> if (err) return err;
>
> writel_relaxed(TSIF_START + ENABLE_IRQ, tsif->base + TSIF_STS_CTL);
> devm_add_action(dev, stop_tsif, tsif);
> INIT_WORK(&tsif->work, handle_pkt);
>
> return 0;
> }
