Hi Dan Carpenter, > -----Original Message----- > From: Dan Carpenter <dan.carpenter@xxxxxxxxxx> > Sent: 16 August 2025 11:28 > Subject: Re: [PATCH 2/4] clk: renesas: rzv2h: Add support for parent mod clocks > > Hi Biju, > > kernel test robot noticed the following build warnings: > > https://git-scm.com/docs/git-format-patch#_base_tree_information] > > url: https://github.com/intel-lab-lkp/linux/commits/Biju/clk-renesas-rzv2h-Refactor- > rzv2h_cpg_fixed_mod_status_clk_register/20250814-205111 > base: https://git.kernel.org/pub/scm/linux/kernel/git/geert/renesas-drivers.git renesas-clk > patch link: https://lore.kernel.org/r/20250814124832.76266-3-biju.das.jz%40bp.renesas.com > patch subject: [PATCH 2/4] clk: renesas: rzv2h: Add support for parent mod clocks > config: hexagon-randconfig-r072-20250815 (https://download.01.org/0day- > ci/archive/20250816/202508160958.ounSAlER-lkp@xxxxxxxxx/config) > compiler: clang version 22.0.0git (https://github.com/llvm/llvm-project > 93d24b6b7b148c47a2fa228a4ef31524fa1d9f3f) > > If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), > kindly add following tags > | Reported-by: kernel test robot <lkp@xxxxxxxxx> > | Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> > | Closes: https://lore.kernel.org/r/202508160958.ounSAlER-lkp@xxxxxxxxx/ > > New smatch warnings: > drivers/clk/renesas/rzv2h-cpg.c:875 rzv2h_cpg_register_mod_clk() warn: passing zero to 'PTR_ERR' > > vim +/PTR_ERR +875 drivers/clk/renesas/rzv2h-cpg.c > > dd22e56217495e Lad Prabhakar 2024-07-29 770 static void __init dd22e56217495e Lad Prabhakar 2024-07- > 29 771 rzv2h_cpg_register_mod_clk(const struct rzv2h_mod_clk *mod, > dd22e56217495e Lad Prabhakar 2024-07-29 772 struct rzv2h_cpg_priv *priv) > dd22e56217495e Lad Prabhakar 2024-07-29 773 { > dd22e56217495e Lad Prabhakar 2024-07-29 774 struct mod_clock *clock = NULL; > dd22e56217495e Lad Prabhakar 2024-07-29 775 struct device *dev = priv->dev; > dd22e56217495e Lad Prabhakar 2024-07-29 776 struct clk_init_data init; > dd22e56217495e Lad Prabhakar 2024-07-29 777 struct clk *parent, *clk; > dd22e56217495e Lad Prabhakar 2024-07-29 778 const char *parent_name; > dd22e56217495e Lad Prabhakar 2024-07-29 779 unsigned int id; > dd22e56217495e Lad Prabhakar 2024-07-29 780 int ret; > dd22e56217495e Lad Prabhakar 2024-07-29 781 > dd22e56217495e Lad Prabhakar 2024-07-29 782 id = GET_MOD_CLK_ID(priv->num_core_clks, mod- > >on_index, mod->on_bit); > dd22e56217495e Lad Prabhakar 2024-07-29 783 WARN_DEBUG(id >= priv->num_core_clks + priv- > >num_mod_clks); > dd22e56217495e Lad Prabhakar 2024-07-29 784 WARN_DEBUG(mod->parent >= priv->num_core_clks + priv- > >num_mod_clks); > dd22e56217495e Lad Prabhakar 2024-07-29 785 WARN_DEBUG(PTR_ERR(priv->clks[id]) != -ENOENT); > dd22e56217495e Lad Prabhakar 2024-07-29 786 > dd22e56217495e Lad Prabhakar 2024-07-29 787 parent = priv->clks[mod->parent]; > dd22e56217495e Lad Prabhakar 2024-07-29 788 if (IS_ERR(parent)) { > dd22e56217495e Lad Prabhakar 2024-07-29 789 clk = parent; > dd22e56217495e Lad Prabhakar 2024-07-29 790 goto fail; > dd22e56217495e Lad Prabhakar 2024-07-29 791 } > dd22e56217495e Lad Prabhakar 2024-07-29 792 > dd22e56217495e Lad Prabhakar 2024-07-29 793 clock = devm_kzalloc(dev, sizeof(*clock), GFP_KERNEL); > dd22e56217495e Lad Prabhakar 2024-07-29 794 if (!clock) { > dd22e56217495e Lad Prabhakar 2024-07-29 795 clk = ERR_PTR(-ENOMEM); > dd22e56217495e Lad Prabhakar 2024-07-29 796 goto fail; > dd22e56217495e Lad Prabhakar 2024-07-29 797 } > dd22e56217495e Lad Prabhakar 2024-07-29 798 > dd22e56217495e Lad Prabhakar 2024-07-29 799 init.name = mod->name; > dd22e56217495e Lad Prabhakar 2024-07-29 800 init.ops = &rzv2h_mod_clock_ops; > dd22e56217495e Lad Prabhakar 2024-07-29 801 init.flags = CLK_SET_RATE_PARENT; > dd22e56217495e Lad Prabhakar 2024-07-29 802 if (mod->critical) > dd22e56217495e Lad Prabhakar 2024-07-29 803 init.flags |= CLK_IS_CRITICAL; > dd22e56217495e Lad Prabhakar 2024-07-29 804 > dd22e56217495e Lad Prabhakar 2024-07-29 805 parent_name = __clk_get_name(parent); > dd22e56217495e Lad Prabhakar 2024-07-29 806 init.parent_names = &parent_name; > dd22e56217495e Lad Prabhakar 2024-07-29 807 init.num_parents = 1; > dd22e56217495e Lad Prabhakar 2024-07-29 808 > dd22e56217495e Lad Prabhakar 2024-07-29 809 clock->on_index = mod->on_index; > dd22e56217495e Lad Prabhakar 2024-07-29 810 clock->on_bit = mod->on_bit; > dd22e56217495e Lad Prabhakar 2024-07-29 811 clock->mon_index = mod->mon_index; > dd22e56217495e Lad Prabhakar 2024-07-29 812 clock->mon_bit = mod->mon_bit; > 03108a2614ecab Lad Prabhakar 2024-12-02 813 clock->no_pm = mod->no_pm; > 899e7ede4c19c6 Lad Prabhakar 2025-05-09 814 clock->ext_clk_mux_index = mod->ext_clk_mux_index; > dd22e56217495e Lad Prabhakar 2024-07-29 815 clock->priv = priv; > dd22e56217495e Lad Prabhakar 2024-07-29 816 clock->hw.init = &init; > 9b6e63a777ea5f Biju Das 2024-12-13 817 clock->mstop_data = mod->mstop_data; > dd22e56217495e Lad Prabhakar 2024-07-29 818 > dd22e56217495e Lad Prabhakar 2024-07-29 819 ret = devm_clk_hw_register(dev, &clock->hw); > dd22e56217495e Lad Prabhakar 2024-07-29 820 if (ret) { > dd22e56217495e Lad Prabhakar 2024-07-29 821 clk = ERR_PTR(ret); > dd22e56217495e Lad Prabhakar 2024-07-29 822 goto fail; > dd22e56217495e Lad Prabhakar 2024-07-29 823 } > dd22e56217495e Lad Prabhakar 2024-07-29 824 > dd22e56217495e Lad Prabhakar 2024-07-29 825 priv->clks[id] = clock->hw.clk; > 18610e6bf54faa Biju Das 2025-08-14 826 if (mod->child_name) { > 18610e6bf54faa Biju Das 2025-08-14 827 WARN_DEBUG(mod->child >= priv->num_core_clks); > 18610e6bf54faa Biju Das 2025-08-14 828 WARN_DEBUG(PTR_ERR(priv->clks[mod->child]) != - > ENOENT); > 18610e6bf54faa Biju Das 2025-08-14 829 > 18610e6bf54faa Biju Das 2025-08-14 830 clk = rzv2h_cpg_mod_status_clk_register(priv, > mod->child_name, mod->name, 1, 1, > 18610e6bf54faa Biju Das 2025-08-14 831 > FIXED_MOD_CONF_PACK(mod->mon_index, > 18610e6bf54faa Biju Das 2025-08-14 832 > mod->mon_bit)); > 18610e6bf54faa Biju Das 2025-08-14 833 if (IS_ERR_OR_NULL(clk)) > 18610e6bf54faa Biju Das 2025-08-14 834 goto fail; > > This isn't how IS_ERR_OR_NULL() is supposed to work... :( The NULL should be treated like success, it > shouldn't print an error message, unless it's something like: OK. > > WARN_ON_ONCE(!clk); // rzv2h_cpg_mod_status_clk_register() is buggy > > I have written a blog about how how IS_ERR_OR_NULL() is supposed to work: > https://staticthinking.wordpress.com/2022/08/01/mixing-error-pointers-and-null/ Thanks for the link. Will take care next time. I would like to drop this patch as Geert provided some feedback to remodel the clocks[1]. [1] https://lore.kernel.org/all/CAMuHMdXJBL_uJ=2v0aKJaSf45070yP=Z_kPe-9uSyE1P0QeiJQ@xxxxxxxxxxxxxx/ Cheers, Biju
