From 5b3c11da141c27df6f8dd8acf90c0046ebab3a07 Mon Sep 17 00:00:00 2001 From: Boris BREZILLON Date: Wed, 2 Oct 2013 14:35:41 +0200 Subject: clocksource: tcb_clksrc: Improve driver robustness Check function return values to avoid false positive driver init. Signed-off-by: Boris BREZILLON Signed-off-by: Daniel Lezcano --- drivers/clocksource/tcb_clksrc.c | 33 ++++++++++++++++++++++++++++----- 1 file changed, 28 insertions(+), 5 deletions(-) diff --git a/drivers/clocksource/tcb_clksrc.c b/drivers/clocksource/tcb_clksrc.c index 048156291fa0..10a5d9ef23f5 100644 --- a/drivers/clocksource/tcb_clksrc.c +++ b/drivers/clocksource/tcb_clksrc.c @@ -184,11 +184,18 @@ static struct irqaction tc_irqaction = { .handler = ch2_irq, }; -static void __init setup_clkevents(struct atmel_tc *tc, int clk32k_divisor_idx) +static int __init setup_clkevents(struct atmel_tc *tc, int clk32k_divisor_idx) { + int ret; struct clk *t2_clk = tc->clk[2]; int irq = tc->irq[2]; + /* try to enable t2 clk to avoid future errors in mode change */ + ret = clk_prepare_enable(t2_clk); + if (ret) + return ret; + clk_disable_unprepare(t2_clk); + clkevt.regs = tc->regs; clkevt.clk = t2_clk; tc_irqaction.dev_id = &clkevt; @@ -197,16 +204,21 @@ static void __init setup_clkevents(struct atmel_tc *tc, int clk32k_divisor_idx) clkevt.clkevt.cpumask = cpumask_of(0); + ret = setup_irq(irq, &tc_irqaction); + if (ret) + return ret; + clockevents_config_and_register(&clkevt.clkevt, 32768, 1, 0xffff); - setup_irq(irq, &tc_irqaction); + return ret; } #else /* !CONFIG_GENERIC_CLOCKEVENTS */ -static void __init setup_clkevents(struct atmel_tc *tc, int clk32k_divisor_idx) +static int __init setup_clkevents(struct atmel_tc *tc, int clk32k_divisor_idx) { /* NOTHING */ + return 0; } #endif @@ -328,13 +340,24 @@ static int __init tcb_clksrc_init(void) } /* and away we go! */ - clocksource_register_hz(&clksrc, divided_rate); + ret = clocksource_register_hz(&clksrc, divided_rate); + if (ret) + goto err_disable_t1; /* channel 2: periodic and oneshot timer support */ - setup_clkevents(tc, clk32k_divisor_idx); + ret = setup_clkevents(tc, clk32k_divisor_idx); + if (ret) + goto err_unregister_clksrc; return 0; +err_unregister_clksrc: + clocksource_unregister(&clksrc); + +err_disable_t1: + if (!tc->tcb_config || tc->tcb_config->counter_width != 32) + clk_disable_unprepare(tc->clk[1]); + err_disable_t0: clk_disable_unprepare(t0_clk); -- cgit