From mboxrd@z Thu Jan 1 00:00:00 1970 From: rnayak@ti.com (Rajendra Nayak) Date: Thu, 17 Nov 2011 14:09:36 +0530 Subject: [PATCH 2/3] omap-serial: Add minimal device tree support In-Reply-To: <4EC3CFDA.1070804@gmail.com> References: <1321441346-19591-1-git-send-email-rnayak@ti.com> <1321441346-19591-3-git-send-email-rnayak@ti.com> <4EC3CFDA.1070804@gmail.com> Message-ID: <4EC4C848.4080800@ti.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Wednesday 16 November 2011 08:29 PM, Rob Herring wrote: > On 11/16/2011 05:02 AM, Rajendra Nayak wrote: >> Adapt the driver to device tree and pass minimal platform >> data from device tree needed for console boot. >> No power management features will be suppported for now >> since it requires more tweaks around OCP settings >> to toggle forceidle/noidle/smaridle bits and handling >> remote wakeup and dynamic muxing. >> >> Signed-off-by: Rajendra Nayak >> --- >> .../devicetree/bindings/serial/omap_serial.txt | 9 +++++ >> drivers/tty/serial/omap-serial.c | 37 +++++++++++++++++++- >> 2 files changed, 45 insertions(+), 1 deletions(-) >> create mode 100644 Documentation/devicetree/bindings/serial/omap_serial.txt >> >> diff --git a/Documentation/devicetree/bindings/serial/omap_serial.txt b/Documentation/devicetree/bindings/serial/omap_serial.txt >> new file mode 100644 >> index 0000000..bf6d631 >> --- /dev/null >> +++ b/Documentation/devicetree/bindings/serial/omap_serial.txt >> @@ -0,0 +1,9 @@ >> +OMAP UART controller >> + >> +Required properties: >> +- compatible : should be "ti,omap-uart" > > This seems too generic. There are no h/w differences in the uart since > the 1st OMAP1 device? This driver supports only OMAP2+ devices, and there doesn't seem to be really much difference. But I might have to re-look, in case I need to handle some silicon errata. > >> +- ti,hwmods : Must be "uart", n being the instance number (1-based) >> + >> +Optional properties: >> +- clock-frequency : frequency of the clock input to the UART >> +- ti,console_hwmod : boolean, UART used as debug console >> diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c >> index e1c8527..e3419c6 100644 >> --- a/drivers/tty/serial/omap-serial.c >> +++ b/drivers/tty/serial/omap-serial.c >> @@ -38,6 +38,7 @@ >> #include >> #include >> #include >> +#include >> >> #include >> #include >> @@ -1322,6 +1323,22 @@ static void uart_tx_dma_callback(int lch, u16 ch_status, void *data) >> return; >> } >> >> +static struct omap_uart_port_info *of_get_uart_port_info(struct device *dev) >> +{ >> + struct omap_uart_port_info *omap_up_info; >> + >> + omap_up_info = devm_kzalloc(dev, sizeof(*omap_up_info), GFP_KERNEL); >> + if (!omap_up_info) >> + return NULL; /* out of memory */ >> + >> + of_property_read_u32(dev->of_node, "clock-frequency", >> + &(*omap_up_info).uartclk); > > &omap_up_info->uartclk > > You want 0 to be the default freq? good point, I need to handle this better. > >> + >> + return omap_up_info; >> +} >> + >> +static atomic_t omap_uart_next_id = ATOMIC_INIT(0); >> + >> static int serial_omap_probe(struct platform_device *pdev) >> { >> struct uart_omap_port *up; >> @@ -1329,6 +1346,11 @@ static int serial_omap_probe(struct platform_device *pdev) >> struct omap_uart_port_info *omap_up_info = pdev->dev.platform_data; >> int ret = -ENOSPC; >> >> + if (pdev->dev.of_node) { >> + omap_up_info = of_get_uart_port_info(&pdev->dev); >> + pdev->id = atomic_inc_return(&omap_uart_next_id) - 1; > > I don't think a driver changing this value is a good idea. Look at other > serial drivers like iMX for how they use aliases. Well, I did lookup, but maybe the wrong one. I looked up the msm serial which added DT support not too long ago and does the exact same thing. > >> + } >> + >> mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); >> if (!mem) { >> dev_err(&pdev->dev, "no mem resource?\n"); >> @@ -1523,7 +1545,7 @@ static int serial_omap_runtime_suspend(struct device *dev) >> if (!up) >> return -EINVAL; >> >> - if (!pdata->enable_wakeup) >> + if (!pdata || !pdata->enable_wakeup) >> return 0; >> >> if (pdata->get_context_loss_count) >> @@ -1582,12 +1604,25 @@ static const struct dev_pm_ops serial_omap_dev_pm_ops = { >> serial_omap_runtime_resume, NULL) >> }; >> >> +#if defined(CONFIG_OF) >> +static const struct of_device_id omap_serial_of_match[] = { >> + { >> + .compatible = "ti,omap-uart", >> + }, >> + {}, >> +}; >> +MODULE_DEVICE_TABLE(of, omap_serial_of_match); >> +#else >> +#define omap_serial_of_match NULL >> +#endif >> + >> static struct platform_driver serial_omap_driver = { >> .probe = serial_omap_probe, >> .remove = serial_omap_remove, >> .driver = { >> .name = DRIVER_NAME, >> .pm =&serial_omap_dev_pm_ops, >> + .of_match_table = omap_serial_of_match, > > Use of_match_ptr and get rid of the #else Ok, thanks. Rajendra > > Rob