PCI: mobiveil: Return bool from link up check

PCIe link status check is supposed to return a boolean to indicate whether
the link is up or not. So update ls_g4_pcie_link_up() to return bool and
also simplify the LTSSM state check.

Signed-off-by: Hans Zhang <18255117159@163.com>
[mani: commit message rewording]
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Niklas Cassel <cassel@kernel.org>
Link: https://patch.msgid.link/20250510160710.392122-3-18255117159@163.com

Author: Hans Zhang

drivers/pci/controller/mobiveil/pcie-layerscape-gen4.c

@@ -53,18 +53,13 @@ static inline void ls_g4_pcie_pf_writel(struct ls_g4_pcie *pcie,
 	iowrite32(val, pcie->pci.csr_axi_slave_base + PCIE_PF_OFF + off);
 }
 
-static int ls_g4_pcie_link_up(struct mobiveil_pcie *pci)
+static bool ls_g4_pcie_link_up(struct mobiveil_pcie *pci)
 {
 	struct ls_g4_pcie *pcie = to_ls_g4_pcie(pci);
 	u32 state;
 
 	state = ls_g4_pcie_pf_readl(pcie, PCIE_PF_DBG);
-	state =	state & PF_DBG_LTSSM_MASK;
-
-	if (state == PF_DBG_LTSSM_L0)
-		return 1;
-
-	return 0;
+	return (state & PF_DBG_LTSSM_MASK) == PF_DBG_LTSSM_L0;
 }
 
 static void ls_g4_pcie_disable_interrupt(struct ls_g4_pcie *pcie)

drivers/pci/controller/mobiveil/pcie-mobiveil.h

@@ -160,7 +160,7 @@ struct mobiveil_root_port {
 };
 
 struct mobiveil_pab_ops {
-	int (*link_up)(struct mobiveil_pcie *pcie);
+	bool (*link_up)(struct mobiveil_pcie *pcie);
 };
 
 struct mobiveil_pcie {