From ceff2676b04943638c6f599ffe4e99efb89aa625 Mon Sep 17 00:00:00 2001 From: John Crispin Date: Fri, 13 Apr 2012 09:37:09 +0200 Subject: [PATCH] SERIAL: MIPS: lantiq: implement OF support Add devicetree and handling for our new clkdev clocks. The patch is rather straightforward. .of_match_table is set and the 3 irqs are now loaded from the devicetree. This series converts the lantiq target to clkdev amongst other things. The driver needs to handle two clocks now. The fpi bus clock used to derive the divider and the clock gate needed on some socs to make the secondary port work. Signed-off-by: John Crispin Acked-by: Greg Kroah-Hartman Cc: Alan Cox Cc: linux-serial@vger.kernel.org Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/3809/ Signed-off-by: Ralf Baechle --- drivers/tty/serial/lantiq.c | 83 +++++++++++++++++++++++-------------- 1 file changed, 51 insertions(+), 32 deletions(-) diff --git a/drivers/tty/serial/lantiq.c b/drivers/tty/serial/lantiq.c index 96c1cacc7360..02da071fe1e7 100644 --- a/drivers/tty/serial/lantiq.c +++ b/drivers/tty/serial/lantiq.c @@ -31,16 +31,19 @@ #include #include #include -#include +#include +#include +#include #include #include +#include #include #define PORT_LTQ_ASC 111 #define MAXPORTS 2 #define UART_DUMMY_UER_RX 1 -#define DRVNAME "ltq_asc" +#define DRVNAME "lantiq,asc" #ifdef __BIG_ENDIAN #define LTQ_ASC_TBUF (0x0020 + 3) #define LTQ_ASC_RBUF (0x0024 + 3) @@ -114,6 +117,9 @@ static DEFINE_SPINLOCK(ltq_asc_lock); struct ltq_uart_port { struct uart_port port; + /* clock used to derive divider */ + struct clk *fpiclk; + /* clock gating of the ASC core */ struct clk *clk; unsigned int tx_irq; unsigned int rx_irq; @@ -316,7 +322,9 @@ lqasc_startup(struct uart_port *port) struct ltq_uart_port *ltq_port = to_ltq_uart_port(port); int retval; - port->uartclk = clk_get_rate(ltq_port->clk); + if (ltq_port->clk) + clk_enable(ltq_port->clk); + port->uartclk = clk_get_rate(ltq_port->fpiclk); ltq_w32_mask(ASCCLC_DISS | ASCCLC_RMCMASK, (1 << ASCCLC_RMCOFFSET), port->membase + LTQ_ASC_CLC); @@ -382,6 +390,8 @@ lqasc_shutdown(struct uart_port *port) port->membase + LTQ_ASC_RXFCON); ltq_w32_mask(ASCTXFCON_TXFEN, ASCTXFCON_TXFFLU, port->membase + LTQ_ASC_TXFCON); + if (ltq_port->clk) + clk_disable(ltq_port->clk); } static void @@ -630,7 +640,7 @@ lqasc_console_setup(struct console *co, char *options) port = <q_port->port; - port->uartclk = clk_get_rate(ltq_port->clk); + port->uartclk = clk_get_rate(ltq_port->fpiclk); if (options) uart_parse_options(options, &baud, &parity, &bits, &flow); @@ -668,37 +678,32 @@ static struct uart_driver lqasc_reg = { static int __init lqasc_probe(struct platform_device *pdev) { + struct device_node *node = pdev->dev.of_node; struct ltq_uart_port *ltq_port; struct uart_port *port; - struct resource *mmres, *irqres; - int tx_irq, rx_irq, err_irq; - struct clk *clk; + struct resource *mmres, irqres[3]; + int line = 0; int ret; mmres = platform_get_resource(pdev, IORESOURCE_MEM, 0); - irqres = platform_get_resource(pdev, IORESOURCE_IRQ, 0); - if (!mmres || !irqres) + ret = of_irq_to_resource_table(node, irqres, 3); + if (!mmres || (ret != 3)) { + dev_err(&pdev->dev, + "failed to get memory/irq for serial port\n"); return -ENODEV; + } - if (pdev->id >= MAXPORTS) - return -EBUSY; + /* check if this is the console port */ + if (mmres->start != CPHYSADDR(LTQ_EARLY_ASC)) + line = 1; - if (lqasc_port[pdev->id] != NULL) + if (lqasc_port[line]) { + dev_err(&pdev->dev, "port %d already allocated\n", line); return -EBUSY; - - clk = clk_get(&pdev->dev, "fpi"); - if (IS_ERR(clk)) { - pr_err("failed to get fpi clk\n"); - return -ENOENT; } - tx_irq = platform_get_irq_byname(pdev, "tx"); - rx_irq = platform_get_irq_byname(pdev, "rx"); - err_irq = platform_get_irq_byname(pdev, "err"); - if ((tx_irq < 0) | (rx_irq < 0) | (err_irq < 0)) - return -ENODEV; - - ltq_port = kzalloc(sizeof(struct ltq_uart_port), GFP_KERNEL); + ltq_port = devm_kzalloc(&pdev->dev, sizeof(struct ltq_uart_port), + GFP_KERNEL); if (!ltq_port) return -ENOMEM; @@ -709,19 +714,26 @@ lqasc_probe(struct platform_device *pdev) port->ops = &lqasc_pops; port->fifosize = 16; port->type = PORT_LTQ_ASC, - port->line = pdev->id; + port->line = line; port->dev = &pdev->dev; - - port->irq = tx_irq; /* unused, just to be backward-compatibe */ + /* unused, just to be backward-compatible */ + port->irq = irqres[0].start; port->mapbase = mmres->start; - ltq_port->clk = clk; + ltq_port->fpiclk = clk_get_fpi(); + if (IS_ERR(ltq_port->fpiclk)) { + pr_err("failed to get fpi clk\n"); + return -ENOENT; + } - ltq_port->tx_irq = tx_irq; - ltq_port->rx_irq = rx_irq; - ltq_port->err_irq = err_irq; + /* not all asc ports have clock gates, lets ignore the return code */ + ltq_port->clk = clk_get(&pdev->dev, NULL); - lqasc_port[pdev->id] = ltq_port; + ltq_port->tx_irq = irqres[0].start; + ltq_port->rx_irq = irqres[1].start; + ltq_port->err_irq = irqres[2].start; + + lqasc_port[line] = ltq_port; platform_set_drvdata(pdev, ltq_port); ret = uart_add_one_port(&lqasc_reg, port); @@ -729,10 +741,17 @@ lqasc_probe(struct platform_device *pdev) return ret; } +static const struct of_device_id ltq_asc_match[] = { + { .compatible = DRVNAME }, + {}, +}; +MODULE_DEVICE_TABLE(of, ltq_asc_match); + static struct platform_driver lqasc_driver = { .driver = { .name = DRVNAME, .owner = THIS_MODULE, + .of_match_table = ltq_asc_match, }, }; -- 2.34.1