From: Jackie Liu liuyun01@kylinos.cn
[ Upstream commit 2aa717473ce96c93ae43a5dc8c23cedc8ce7dd9f ]
The s3c24xx_init_intc() returns an error pointer upon failure, not NULL. let's add an error pointer check in s3c24xx_handle_irq.
s3c_intc[0] is not NULL or ERR, we can simplify the code.
Fixes: 1f629b7a3ced ("ARM: S3C24XX: transform irq handling into a declarative form") Signed-off-by: Jackie Liu liuyun01@kylinos.cn Link: https://lore.kernel.org/r/20210901123557.1043953-1-liu.yun@linux.dev Signed-off-by: Krzysztof Kozlowski krzysztof.kozlowski@canonical.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/irqchip/irq-s3c24xx.c | 22 ++++++++++++++++++---- 1 file changed, 18 insertions(+), 4 deletions(-)
diff --git a/drivers/irqchip/irq-s3c24xx.c b/drivers/irqchip/irq-s3c24xx.c index d2031fecc3861..5e97ae54782d6 100644 --- a/drivers/irqchip/irq-s3c24xx.c +++ b/drivers/irqchip/irq-s3c24xx.c @@ -359,11 +359,25 @@ static inline int s3c24xx_handle_intc(struct s3c_irq_intc *intc, asmlinkage void __exception_irq_entry s3c24xx_handle_irq(struct pt_regs *regs) { do { - if (likely(s3c_intc[0])) - if (s3c24xx_handle_intc(s3c_intc[0], regs, 0)) - continue; + /* + * For platform based machines, neither ERR nor NULL can happen here. + * The s3c24xx_handle_irq() will be set as IRQ handler iff this succeeds: + * + * s3c_intc[0] = s3c24xx_init_intc() + * + * If this fails, the next calls to s3c24xx_init_intc() won't be executed. + * + * For DT machine, s3c_init_intc_of() could set the IRQ handler without + * setting s3c_intc[0] only if it was called with num_ctrl=0. There is no + * such code path, so again the s3c_intc[0] will have a valid pointer if + * set_handle_irq() is called. + * + * Therefore in s3c24xx_handle_irq(), the s3c_intc[0] is always something. + */ + if (s3c24xx_handle_intc(s3c_intc[0], regs, 0)) + continue;
- if (s3c_intc[2]) + if (!IS_ERR_OR_NULL(s3c_intc[2])) if (s3c24xx_handle_intc(s3c_intc[2], regs, 64)) continue;