From be280fddfd645ea0ce4c7a26692c3d1115447e32 Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Mon, 12 Aug 2024 11:29:38 +0300 Subject: drm/ast: astdp: fix loop timeout check This code has an issue because it loops until "i" is set to UINT_MAX but the test for failure assumes that "i" is set to zero. The result is that it will only print an error message if we succeed on the very last try. Reformat the loop to count forwards instead of backwards. Fixes: 2281475168d2 ("drm/ast: astdp: Perform link training during atomic_enable") Signed-off-by: Dan Carpenter Reviewed-by: Thomas Zimmermann Signed-off-by: Thomas Zimmermann Link: https://patchwork.freedesktop.org/patch/msgid/1ba8da25-2d09-4924-a4ff-c0714bfbb192@stanley.mountain --- drivers/gpu/drm/ast/ast_dp.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) (limited to 'drivers') diff --git a/drivers/gpu/drm/ast/ast_dp.c b/drivers/gpu/drm/ast/ast_dp.c index 5d07678b502c..ca022c287785 100644 --- a/drivers/gpu/drm/ast/ast_dp.c +++ b/drivers/gpu/drm/ast/ast_dp.c @@ -146,18 +146,19 @@ void ast_dp_power_on_off(struct drm_device *dev, bool on) void ast_dp_link_training(struct ast_device *ast) { struct drm_device *dev = &ast->base; - unsigned int i = 10; + int i; - while (i--) { - u8 vgacrdc = ast_get_index_reg(ast, AST_IO_VGACRI, 0xdc); + for (i = 0; i < 10; i++) { + u8 vgacrdc; - if (vgacrdc & AST_IO_VGACRDC_LINK_SUCCESS) - break; if (i) msleep(100); + + vgacrdc = ast_get_index_reg(ast, AST_IO_VGACRI, 0xdc); + if (vgacrdc & AST_IO_VGACRDC_LINK_SUCCESS) + return; } - if (!i) - drm_err(dev, "Link training failed\n"); + drm_err(dev, "Link training failed\n"); } void ast_dp_set_on_off(struct drm_device *dev, bool on) -- cgit