From e149b42b8605f4e0e86662fe880716ccdfdb4ef9 Mon Sep 17 00:00:00 2001 From: Gerhard Sittig Date: Sat, 30 Nov 2013 23:51:29 +0100 Subject: serial: mpc512x: adjust for OF based clock lookup after device tree based clock lookup became available, the peripheral driver need no longer construct clock names which include the PSC index, remove the "psc%d_mclk" template and unconditionally use 'mclk' acquire and release the "ipg" clock item for register access as well Cc: Greg Kroah-Hartman Cc: Jiri Slaby Cc: linux-serial@vger.kernel.org Acked-by: Greg Kroah-Hartman Signed-off-by: Gerhard Sittig Signed-off-by: Anatolij Gustschin --- drivers/tty/serial/mpc52xx_uart.c | 40 ++++++++++++++++++++++++++++++++++----- 1 file changed, 35 insertions(+), 5 deletions(-) (limited to 'drivers/tty/serial') diff --git a/drivers/tty/serial/mpc52xx_uart.c b/drivers/tty/serial/mpc52xx_uart.c index ec06505..6345f37 100644 --- a/drivers/tty/serial/mpc52xx_uart.c +++ b/drivers/tty/serial/mpc52xx_uart.c @@ -619,29 +619,55 @@ static irqreturn_t mpc512x_psc_handle_irq(struct uart_port *port) } static struct clk *psc_mclk_clk[MPC52xx_PSC_MAXNUM]; +static struct clk *psc_ipg_clk[MPC52xx_PSC_MAXNUM]; /* called from within the .request_port() callback (allocation) */ static int mpc512x_psc_alloc_clock(struct uart_port *port) { int psc_num; - char clk_name[16]; struct clk *clk; int err; psc_num = (port->mapbase & 0xf00) >> 8; - snprintf(clk_name, sizeof(clk_name), "psc%d_mclk", psc_num); - clk = devm_clk_get(port->dev, clk_name); + + clk = devm_clk_get(port->dev, "mclk"); if (IS_ERR(clk)) { dev_err(port->dev, "Failed to get MCLK!\n"); - return PTR_ERR(clk); + err = PTR_ERR(clk); + goto out_err; } err = clk_prepare_enable(clk); if (err) { dev_err(port->dev, "Failed to enable MCLK!\n"); - return err; + goto out_err; } psc_mclk_clk[psc_num] = clk; + + clk = devm_clk_get(port->dev, "ipg"); + if (IS_ERR(clk)) { + dev_err(port->dev, "Failed to get IPG clock!\n"); + err = PTR_ERR(clk); + goto out_err; + } + err = clk_prepare_enable(clk); + if (err) { + dev_err(port->dev, "Failed to enable IPG clock!\n"); + goto out_err; + } + psc_ipg_clk[psc_num] = clk; + return 0; + +out_err: + if (psc_mclk_clk[psc_num]) { + clk_disable_unprepare(psc_mclk_clk[psc_num]); + psc_mclk_clk[psc_num] = NULL; + } + if (psc_ipg_clk[psc_num]) { + clk_disable_unprepare(psc_ipg_clk[psc_num]); + psc_ipg_clk[psc_num] = NULL; + } + return err; } /* called from within the .release_port() callback (release) */ @@ -656,6 +682,10 @@ static void mpc512x_psc_relse_clock(struct uart_port *port) clk_disable_unprepare(clk); psc_mclk_clk[psc_num] = NULL; } + if (psc_ipg_clk[psc_num]) { + clk_disable_unprepare(psc_ipg_clk[psc_num]); + psc_ipg_clk[psc_num] = NULL; + } } /* implementation of the .clock() callback (enable/disable) */ -- cgit v1.1 From cb1ea81230f0b5593b847d2cb3d9304e1d5e4234 Mon Sep 17 00:00:00 2001 From: Gerhard Sittig Date: Sat, 30 Nov 2013 23:51:30 +0100 Subject: serial: mpc512x: setup the PSC FIFO clock as well prepare and enable the FIFO clock upon PSC FIFO initialization, check for and propagage errors when enabling the PSC FIFO clock, disable and unprepare the FIFO clock upon PSC FIFO uninitialization devm_{get,put}_clk() doesn't apply here, as the SoC provides a single FIFO component which is shared among several PSC components, thus the FIFO isn't associated with a device (while the PSCs are) provide a fallback clock lookup approach in case the OF based clock lookup for the PSC FIFO fails, this allows for successful operation in the presence of an outdated device tree which lacks clock specs Cc: Greg Kroah-Hartman Cc: Jiri Slaby Cc: linux-serial@vger.kernel.org Acked-by: Greg Kroah-Hartman Signed-off-by: Gerhard Sittig Signed-off-by: Anatolij Gustschin --- drivers/tty/serial/mpc52xx_uart.c | 50 ++++++++++++++++++++++++++++++++++----- 1 file changed, 44 insertions(+), 6 deletions(-) (limited to 'drivers/tty/serial') diff --git a/drivers/tty/serial/mpc52xx_uart.c b/drivers/tty/serial/mpc52xx_uart.c index 6345f37..97888f4 100644 --- a/drivers/tty/serial/mpc52xx_uart.c +++ b/drivers/tty/serial/mpc52xx_uart.c @@ -421,6 +421,7 @@ struct psc_fifoc { static struct psc_fifoc __iomem *psc_fifoc; static unsigned int psc_fifoc_irq; +static struct clk *psc_fifoc_clk; static void mpc512x_psc_fifo_init(struct uart_port *port) { @@ -568,36 +569,73 @@ static unsigned int mpc512x_psc_set_baudrate(struct uart_port *port, /* Init PSC FIFO Controller */ static int __init mpc512x_psc_fifoc_init(void) { + int err; struct device_node *np; + struct clk *clk; + + /* default error code, potentially overwritten by clock calls */ + err = -ENODEV; np = of_find_compatible_node(NULL, NULL, "fsl,mpc5121-psc-fifo"); if (!np) { pr_err("%s: Can't find FIFOC node\n", __func__); - return -ENODEV; + goto out_err; + } + + clk = of_clk_get(np, 0); + if (IS_ERR(clk)) { + /* backwards compat with device trees that lack clock specs */ + clk = clk_get_sys(np->name, "ipg"); + } + if (IS_ERR(clk)) { + pr_err("%s: Can't lookup FIFO clock\n", __func__); + err = PTR_ERR(clk); + goto out_ofnode_put; + } + if (clk_prepare_enable(clk)) { + pr_err("%s: Can't enable FIFO clock\n", __func__); + clk_put(clk); + goto out_ofnode_put; } + psc_fifoc_clk = clk; psc_fifoc = of_iomap(np, 0); if (!psc_fifoc) { pr_err("%s: Can't map FIFOC\n", __func__); - of_node_put(np); - return -ENODEV; + goto out_clk_disable; } psc_fifoc_irq = irq_of_parse_and_map(np, 0); - of_node_put(np); if (psc_fifoc_irq == 0) { pr_err("%s: Can't get FIFOC irq\n", __func__); - iounmap(psc_fifoc); - return -ENODEV; + goto out_unmap; } + of_node_put(np); return 0; + +out_unmap: + iounmap(psc_fifoc); +out_clk_disable: + clk_disable_unprepare(psc_fifoc_clk); + clk_put(psc_fifoc_clk); +out_ofnode_put: + of_node_put(np); +out_err: + return err; } static void __exit mpc512x_psc_fifoc_uninit(void) { iounmap(psc_fifoc); + + /* disable the clock, errors are not fatal */ + if (psc_fifoc_clk) { + clk_disable_unprepare(psc_fifoc_clk); + clk_put(psc_fifoc_clk); + psc_fifoc_clk = NULL; + } } /* 512x specific interrupt handler. The caller holds the port lock */ -- cgit v1.1